I Can Read Faces! My Wager On The Election Results

On the eve of Election Day, I am a happy man.  Why is this, you ask?  Because the fundamentals-based forecasts issued by almost a  dozen political scientists before Labor Day are – in the aggregate – looking remarkably prescient. The average prediction of those eleven models has Obama winning 50.3% of the two-party vote, while the median gives him 50.6%.  So far, these forecasts seem to be holding up quite well, with both the RealClearPolitics and Pollster.com aggregate national poll showing this race, as measured by the popular vote, as essentially a dead heat, one day before the election.  Score one for political science!

Of course, that doesn’t tell us who is going to win, which is what most of you want to know.  Fear not!  We need only consult the state-based forecasts issued by Drew Linzer, Sam Wang, Simon Jackman, and Tom Holbrook and Jay DeSart.  (There are others out there, but these are the ones whose methods are most transparent, and with which I am most familiar.  If you want a bit of background on their methods, see this article on “the rise of the quants” ).  Although these forecast models differ in some of the particulars (whether to compensate for a pollster’s “house effect”, how to weight the state polls, the relative weight place on polls of likely vs. registered voters, etc.), they all operate on the same assumption: that state-based polls, taken in the aggregate, provide a very accurate indicator of who is going to win that state, particularly this late in the game.  That, in turn, makes it relatively easy to put together an Electoral College forecast.  All of them have done so, and as I’ve discussed in an earlier post, they all see it as more likely that Obama wins the Electoral College vote.  This doesn’t mean they believe Romney can’t win – they just see it as less probable than an Obama victory.

The process by which these political scientists (Wang is actually a neuroscientist, but he gets honorary membership) put together their predictions is in stark contrast to the methods used by the traditional pundits.  Consider this projection by Jay Cost, a very smart analyst who writes for the Weekly Standard.  Cost believes Romney will win this election, and in explaining why, he took a shot at political science forecast models:  “Both political science and the political polls too often imply a scientific precision that I no longer think actually exists in American politics. I have slowly learned that politics is a lot more art than science than I once believed. Accordingly, what follows is a prediction based on my interpretation of the lay of the land. I know others see it differently–and they could very well be right, and I could be wrong. I think Mitt Romney is likely to win next Tuesday.” As evidence for his prediction, Cost cites two points: Romney is leading among independents, and most voters think he will do a better job handling the economy.

Cost is not alone in thinking that Romney is going to win – there are some very smart people who have vast experience in electoral politics who agree with him.  Here is a list of the most prominent political pundits, and their predictions.   However, as I scan the list, I can’t help but notice that the bulk of people who agree with Cost in predicting a Romney victory are conservatives, including Karl Rove, Glenn Beck, Ari Fleischer, Jay Cost, Peggy Noonan and Dick Morris. On the other hand, many of the best-known liberal pundits – Markos Moulitsas, Jamelle Bouie, Jennifer Granholm, Donna Brazile and Cokie Roberts – think Obama will win.  Now, all of them claim to be looking at the same data – the same polls, the same candidate strategies, the same advertisements, etc.   How, then, can we explain why they end up with dramatically different predictions?  More generally, why do liberals think Obama will win, and conservatives think Romney will?

The answer, I think, is that people – liberals, conservatives and everyone else – are very good at seeing patterns in data that suggest outcomes that conform to their preferences.  Mind you – these aren’t implausible patterns – indeed, what makes them so seductive is that they are very plausible.  Cost, for instance, is correct that most polls indicate that Romney is viewed as better able to handle the economy.  But notice what he writes: “Poll after poll, I generally see the same thing. Romney has an edge on the economy. That includes most of the state polls.”  At the same time, however, he evidently is discounting those same state polls that, looked at in the aggregate by political scientists, indicate that Obama is more likely to win the Electoral College.  So, the question becomes: why value what the state polls say in one area – Romney’s handling of the economy – while discounting their overall projections that say Romney is more likely to lose?

The worry I have when analysts “interpret” data is that it leaves room for personal preferences to sneak in.  Taken to an extreme, it leads to far-fetched inferences like this one tweeted earlier today by Peggy Noonan: “I suspect both Romney and Obama have a sense of what’s coming, and it’s part of why Romney looks so peaceful and Obama so roiled.”  Really?  She can see the election outcome by “reading” their faces?  This presumes that both Obama and Romney know “what is coming” – highly unlikely in a 50/50 race- and that she has some method – a sixth sense? – for inferring when facial expressions reveal a person’s inner thoughts.  Maybe she can see dead people too.

Ok. That was a cheap shot. Let me be clear. I think Noonan is a very smart person.  Her memoir of her years as a Reagan speechwriter is one of the best accounts of life in the White House that I’ve ever read.  But I don’t believe she can read faces.

And that leads me to my broader point.  When I consider this latest election cycle, the most important development in how it has been covered, in my view, is the growing prominence of analysts whose methods are both more rigorous and more data-driven than what we are used to seeing from traditional “pundits”.  I think we are witnessing a sea change in political analysis, one that will leave an indelible mark on future coverage of presidential elections.  Increasingly, the traditional seat-of-the-pants, intuition-based method of analyzing elections is giving way to a less impressionistic mode of analysis. To be sure, these new methods are not infallible by any means. But they are a step forward. And political scientists are leading that movement.

To be fair to Cost, and Noonan, and all the rest of the “traditional” pundits, and the new ones too – they at least had the courage to put their professional reputations on the line and make a prediction.  So I am going to do the same – tomorrow morning.   I can tell you now – my prediction will be entirely atheoretical, and will be based on the latest state-based polling averages.  But to make it interesting, I will make a wager:  if my prediction regarding the winner tomorrow is incorrect, I will pay the bar bill (alcohol only) for everyone who attends the Election Night at the Grille, which Bert Johnson and I will be hosting.  So keep your receipts!  The festivities start at 7 p.m. and, as always, I’ll be living blogging the election returns while keeping the crowd at the Karl Rove Crossroads cafe – er, the Grille – entertained as well.  For those in the area, I hope to see you tomorrow night.  For the rest of you, please join me at this site.  We are hoping to break our all time record for participation.

I’ll see you tomorrow.

The Pundits vs. Political Science: Debating the Impact of the First Debate

As Election 2012 heads down to the wire, it is fascinating to see how the pundits view this race compared to where the political scientists do (at least as I interpret them).  They often seem to be looking at two different events.  For pundits, the race is a roller-coaster affair in which candidates gain and lose momentum based on a series of often unpredictable events.  Thus, on today’s Meet the Press, Joe Scarborough openly speculated about the impact of Hurricane Sandy in blunting Romney’s “momentum.” In Scarborough’s words, “The question is, whether the hurricane stopped the momentum for 48 hours and whether that in the end will stop him from overtaking the president.”

The only problem with this analysis is that it appears that Mitt’s support had stabilized at between 47-48% in the national polls back on October 9, and there hasn’t been very much movement beyond random statistical fluctuations since then.  In other words, there wasn’t much momentum for Mitt to lose, Sandy or no Sandy.

David Gregory, the host, then asked his panelists to identify the moments of the campaign that stood out to them.   Four of the five participants cited the first debate as the turning point in this campaign.  Scarborough, taking what might be perceived as a shot at political scientists, argued, “And, third, just a remarkable first debate that if Mitt Romney wins will be a debate that political scientists will be looking at fifty years from now.  It really could be the big turning point.”  The usually reliable Tom Brokaw concurred: “I– I think the first debate.  I think that history will long record that if he survives this– that debate was something unprecedented.  I have never seen anything like that in my lifetime, when a man who had to convince the country, he was a strong leader, disappeared from that stage.”

At this risk of repeating myself (see here and here), there is not much evidence that the first debate had nearly the impact the pundits ascribe to it.  Previously I published Anna Esten’s research indicating that Mitt may have earned a net gain of about 2.7% when comparing the average of the polls in the week prior to the first debate compared to the average of those polls in the week after.  This is not an inconsequential gain, mind you, but it’s worth remembering what that change signifies.  As I’ve argued before, that net gain did not come from converting Obama supporters to Romney supporters – instead, it came from shifting the proportion of people who made it through the various polling voter screens. In short, the first debate was a focusing event that likely accelerated the polling toward the dead-heat equilibrium that the political science forecast models, looked at in the aggregate, have been suggesting this race would become all along.

Moreover as Peter Kellner explains in this post, there is some evidence, based on looking at a panel study that interviewed the same set of people both pre- and post-debate,  that even a 2.7% projected net gain for Mitt may overstate the impact of the first debate.  Kellner writes, “The key point is that this was a true panel study. We questioned the same people twice. This allowed us to investigate what change, if any, took place at the level of individual voters, NOT by comparing results from different samples.  Any change in the numbers in such panel studies reflects real changes by real voters. And our overall sample was much larger than normal. We polled almost 33,000 electors in September, and reinterviewed more than 25,000 of them after the first debate.

The message from this study was clear. The Romney bounce was tiny.  Overall, YouGov found just a one-point narrowing of Obama’s lead.”

Why did YouGov find only a 1% change, while Anna calculated Mitt gained a more sizeable advantage? The answer gets to an issue I’ve talked about before – most pollsters do not “weight” their polls to maintain a fixed proportion of partisans.  That is, they let the poll results determine how many “Democrats” and “Republicans” there are in any particular sample.  So, after the first debate, many pollsters likely picked up a shift in party identification indicating more Republican self-identifiers, which in turn suggested a net polling gain for Romney. The debate had the same impact on the YouGov panel study – more Republicans in the panel were likely to answer the follow up survey after the first debate than were Democrats.  However, in contrast, to most pollsters, YouGov adjusted their post-debate sample to keep the partisan distribution consistent with the pre-debate sample.  When they did that, they saw only minimal gains by Mitt.

Kellner’s conclusion?  “What we can therefore be fairly sure of is that the first TV debate made little or no difference to the (high) degree of loyalty Democrats and Republicans display towards the two candidates. It is NOT the case that many voters switched from Obama to Romney. The question, rather, is whether the first debate caused the number of Democratic-ID Americans to fall, and Republican-ID Americans to rise.”

The answer to just how big an impact that first debate had, then, turns in part on whether you think “partisanship” changes only slowly, or that it can in fact change rapidly in response to a single event, such as a debate.  Note that this is not one of those nerd fights that have little consequence in the real world.  Instead, it gets to the heart of the polling discrepancies we have found between some state-level polls and the national tracking polls by some firms, like Rasmussen, that do adjust their partisan composition to bring it in line with what they think the “true” party division currently is.  Decisions regarding whether and how to weight by party can determine whether a poll favors one candidate or the other.  Republicans have consistently argued that many pollsters are including too many Democrats in their samples. Democrats counter that some firms, like Gallup, are underweighting some groups that are likely to vote Democratic.  We will know who is right on Tuesday.

Meanwhile, in the long run,  I suspect Scarborough is right. Fifty years from now political scientists will be arguing that the first Romney-Obama debate didn’t have nearly the impact the media pundits said it did – and we will be ignored then as well!

Who Is Really Winning This Race?

Because I have been giving election talks with more frequency of late, I haven’t been able to post nearly as often as I would like.  In giving those talks, however, I am reminded (and I remind my audiences!) that, once again, looked at in the aggregate, the structural-based political science forecast models issued by Labor Day (or earlier) have proved remarkably  accurate.  For those new to this blog, the median forecast of the 11 political science forecast models that I reviewed in previous posts gave Obama 50.6% of the two-party vote.  The average forecast from those 11 models gave Obama 50.3% of the two-party vote.  Remember, this was before the debates, the tax returns, the “gaffes”, and all the other events cited by various pundits as potential game changers.  As of today, that aggregate median forecast (those who attend my talks will remember that the aggregate median forecast provides the basis of my election prediction) from two months ago looks like it will come very close to hitting the final Obama popular vote share squarely on the head if the national tracking polls are to be believed. This is no mean feat, in my book, and it is a reminder that political scientists have developed a decent understanding of the factors that drive presidential election outcomes.  It is reassuring that this election cycle has proved remarkably unsurprising in terms of its likely outcome.

Of course, while those structural models may be correct in predicting this race would essentially be a dead heat, they don’t tell us who is going to win, which is what most people want to know.  At this point, five days before the election, you are better off looking at the polls – state and national – which are probably going to be more accurate than structural models devised several months ago in predicting the winner (even if they are going to be far less useful in understanding why Obama, or Romney, won).  Several political scientists (and others) have developed Electoral College forecast models based on state-level polls, in contrast to the structural models which ignore polls entirely.  I present four of these state-based projections here. (Readers will remember that if I can’t see what goes into a prediction model, I don’t bother following its projections.  That’s a basic tenet among academics, and it explains why I ignore some of the more highly publicized state-based forecast models. )

As you can see, all four of these forecasts show, as of today, that Obama is likely to win the Electoral College vote, based on state-level polls.  This has led pundits at some sites, like this one at Mother Jones, to suggest that if all these prognosticators are predicting an Obama victory, it must be so.  But it would be a mistake to treat these forecasts as independent assessments.  In fact, all rely on the same set of state-level polls, and if the polls are wrong for some reason, all of the projections will be off as well.  Moreover, as several commentators have noted, the national tracking polls tell a slightly different story.  Consistent with the structural forecast models, they indicate that this race is actually a dead heat.   Indeed, some pundits, like Pollster.com’s Steve Lombardo, are convinced that the national tracking polls indicate that Romney is poised to win the national popular vote.  Lombardo writes,” Our current estimate (which we will update next Tuesday morning) suggests that Romney will capture 51 percent of the popular vote to Obama’s 48.5 percent. The trend line-based on 26 national polls conducted over the last 30 days –is both unmistakable and virtually unassailable.”

If Lombardo is right, there is virtually no chance that Obama will win the Electoral College vote.  The problem with this projection is that Lombardo assumes the trajectory of the trend line will continue unabated through Election Day. My read of the latest national tracking polls, however, suggests that Romney’s “momentum” has dissipated, and that the race has settled into a rather stable equilibrium, with neither candidate showing an advantage.   As evidence, consider the latest RCP composite poll, which shows the race essentially tied.

I have said all along that the state-level polls and the national polls will gradually converge.  But in whose favor?  In my next post, I’ll address evidence suggesting that Romney may benefit from an “enthusiasm” advantage among Republican voters. In the meantime, however, it is worth remembering that, once again, the “composite” political science forecast reveals that presidential elections are rather predictable affairs and that contrary to what some pundits have suggested, this election has – to date – contained few surprises.

So, who is really winning this race?  As of today, it is political scientists.

Different Forecast, Same Result: More Political Science Models

Politico’s Dylan Byers created a minor dust-up in the twitterverse today when he posted an article that appeared to take a shot at the New York Times’  Nate Silver’s prognosticating skills. Byers writes, “Prediction is the name of Silver’s game, the basis for his celebrity. So should Mitt Romney win on Nov. 6, it’s difficult to see how people can continue to put faith in the predictions of someone who has never given that candidate anything higher than a 41 percent chance of winning (way back on June 2) and — one week from the election — gives him a one-in-four chance, even as the polls have him almost neck-and-neck with the incumbent.”  Byers’ article almost immediately created pushback from others who pointed out that the win probability is not the same as projecting a popular vote percentage.

That distinction is likely lost on many Romney supporters who have been criticizing Silver’s forecast for some time now.  But while Silver’s highly publicized work has attracted many Republicans’ ire, it is important to realize that several political scientists have developed their own state-based forecast models that are every bit as good as Silver’s and have the added virtue of being completely transparent and which have been vetted by other political scientists.  Those models are, as of today, also forecasting an Obama Electoral College victory.

In my last post I discussed one such model – the one developed by Emory political scientist Drew Linzer and featured at his Votamatic website.  As of today, Linzer’s state-based polling model continues to forecast an Electoral College victory for Obama with 332 Electoral College votes to Romney’s 206. I’ve discussed some of the assumptions built into Drew’s model in a previous post.

Today I want to discuss a second state-based forecast model created by political scientists Tom Holbrook and Jay DeSart.  Their model is even simpler and more parsimonious than Drew’s. Essentially, they look at three variables: the average Democratic vote share in all trial-heat polls in the field during October, the average Democratic share of the two-party support in national polls taken in the October prior to the election, and the average Democratic two-party state vote share in the four previous presidential elections. Like Drew’s model, then, they are incorporating both a long-term factor – the previous state-level election results that provide a window into a state’s ideological leanings – and short-term factors captured by the October state-level polls during the current election year together with the candidate’s standing in the national polls.

In 2008, the model successfully called all but 3 states: Missouri, North Carolina and Indiana.  (It’s not clear to me what they did for the split vote in Nebraska.) This prediction isn’t quite in Sam Wang territory (Sam nailed everything but Nebraska, as I recall), but it’s not too shabby either.

For those of you interested in playing at home, here’s the equation for their 2012 forecast model:

VOTEi = -29.454 + .575(POLL)i + 0.57(PRIOR VOTE)i + .44(NATIONAL POLL).

As of today that model is also projecting an Obama Electoral College victory, but by a closer margin, 281-257, than the Votamatic projection. Despite the closer Electoral College projection, they still estimate that Obama’s win probability is more than 86%.  Here are the current state-by-state projections:

Obama

Romney

State

Win
Probability

State

Win
Probability

Ohio

67.8

Colorado

50.5

New Hampshire

72.0

Florida

52.7

Nevada

74.4

Virginia

55.0

Iowa

76.8

North Carolina

81.4

Wisconsin

83.6

Arizona

92.0

Pennsylvania

88.7

Missouri

95.0

Michigan

93.6

Georgia

97.5

Minnesota

96.1

South Dakota

97.8

Oregon

97.4

Montana

99.3

New Mexico

98.4

South Carolina

99.7

Maine

99.5

Indiana

99.9

Washington

99.7

Kentucky

100

New Jersey

99.8

Tennessee

100

Connecticut

99.9

Texas

100

California

100

Mississippi

100

Delaware

100

West Virginia

100

Illinois

100

Kansas

100

Maryland

100

Nebraska

100

Massachusetts

100

North Dakota

100

New York

100

Louisiana

100

Rhode Island

100

Arkansas

100

Hawaii

100

Oklahoma

100

Vermont

100

Alabama

100

DC

100

Alaska

100

Wyoming

100

Idaho

100

Utah

100

Note that according to these win probabilities, it is more likely that Obama would “win back” Virginia, Florida or Colorado than it is that Mitt can take Ohio. Indeed, those are the three states that Drew currently has in Obama’s column.  That’s a total of 51 Electoral College votes in those three states alone, and it is the difference between Obama winning 281 Electoral College votes versus 332.  So clearly these forecasts are amenable to change, even with the dwindling number of undecideds.  Given the close nature of the race, several states can tip in either direction.  However, both models suggest that, based on current state polling, Romney has a bigger hurdle ahead of him if he is going to pull this out.

I want to stress that these models use the latest polling in each state to project the winner.   As such, they tend to be more accurate than the structural forecast models political scientists issue by Labor Day based on the “fundamentals” that I’ve discussed in several previous posts.  The drawback, of course, is that these state-based models don’t help us understand why people are voting for a particular candidate.  In effect, they use current support to predict future support.  That works well if all one is interested in is predicting the election outcome, but they aren’t very theoretically satisfying.

Note that both the Linzer and the Holbrook-DeSart models are premised on the assumption that state-based polls this late in the year are generally accurate.  Is that a safe premise?  In fact, as John Sides discusses here citing research by Robert Ericksen and Christopher Wezlien, they are.  As this graph shows, the share of the Democratic vote based on polls in the last week of the election closely aligns to the actual vote percentage received by the Democratic candidate in the period 1952-2008. (If the alignment was perfect, the data points would fall directly on the diagonal line.)

So, using conceptually simple (and transparent!) methods, political scientists still see this race as Obama’s to lose. This does not mean, however, that this election is over.  The key – and as yet unanswered – question is whether Mitt can, through a combination of winning over undecided voters and gaining a turnout advantage, rope in the 1-2% more support he needs to flip Ohio, or some other combination of swing states.   Your answer to that question may depend on whether you think there continues to be movement toward Romney, however slight, during these last eight days. If there is, both models should pick this up, and adjust their projections accordingly.  If there is not, however, and this race has entered a stable equilibrium, the odds seem to be in Obama’s favor.

P.S If you are coming to this site for the first time (there’s been a lot of traffic of late) I encourage you to follow me on Twitter at @MattDickinson44 – I tweet all new posts there.

 

How True Drew? Linzer Still Sees Obama As A Heavy Favorite

Emory University political scientist Drew Linzer, who created and runs the Votamatic website, paid a visit to Middlebury College last Wednesday to discuss why, based on his forecast model, he believes President Obama is still the heavy favorite to win the presidential election.  To construct his model, Drew uses his colleague Alan Abramowitz’ “Time for A Change”  forecast model as his baseline starting point.  You will recall from one of my earlier posts that Abramowitz’s forecast model uses three factors — the incumbent president’s net approval rating at the end of June, the change in real GDP in the second quarter of the election year and a first-term incumbency advantage — to predict the winner of the national popular vote.  However, during the current election cycle Abramowitz updated his traditional model to include a “polarization” variable that, in effect, reduces the advantage enjoyed by a first-term incumbent running for reelection by about half – from a bit more than 5% to closer to 2.5%.  Under his “new” model, Abramowitz projects Obama’s share of the two-party vote to be about 50.3%.

As I’ve discussed before, not everyone accepts Abramowitz’s rationale for updating his model.  Drew is one of the skeptics, and so his forecast model starts with the “old” Abramowitz model which is decidedly more bullish regarding Obama’s chances.  Without the polarization variable, Abramowitz’s structural baseline component has Obama winning 52.2% of the two-party national vote.  That’s a much stronger starting advantage for the President than the “new” Abramowitz model suggests.

The second component in Drew’s model is the state-based polls, which he uses to “update” the Abramowitz baseline forecast. As we get closer to Election Day, state-level survey data influences his projection more and more, and Abramowitz’s structural component becomes correspondingly less important.  At this point, 10 days out, the state-level polling component is really driving his forecast almost entirely.

So, where does the race stand, according to Drew’s model?   As I discussed in my Economist post, as of today, he projects Obama to win 332 Electoral College votes, or 62% of the 538 Electoral College votes, compared to Romney’s 206.

Note that Drew makes several assumptions in his model.  First, he makes no effort to adjust for the “house effects” of individual polls in the belief that in the closest states that are polled most frequently, polling biases will largely cancel out.   Second, he essentially assumes that the “undecideds” will break in rough proportion to the distribution of the vote, as indicated by the polls, in each state.  Third, since he is interested in forecasting the Electoral College vote, he pays no attention to national tracking polls.

It is doubtful that Drew, or anyone, could have constructed such a forecast model even eight years ago.  But the proliferation of state polls, particularly in contested states, now allows political scientists to adjust their structural models in light of recent polling on a state-by-state basis.   Of course, this type of modeling is in its infancy; Drew only has one previous election cycle, in 2008, to calibrate his assumptions.

I asked Drew what would happen if he changed his baseline starting point by, for example, substituting Doug Hibbs’ Bread and Peace forecast model, which predicts that Obama will win closer to 47% of the two-party vote – or about 5% below the Abramowitz projection.  Drew acknowledged that this would shift the baseline parameter enough to move several swing states into Romney’s column.   Nonetheless, based on a state-by-state electoral projection and given the current polling, even with this shift Drew does not believe that Romney would gain enough Electoral College votes to overcome Obama’s current projected advantage.

Is Drew right?  Remember, for some time now I have been arguing that the state-level polls will gradually align with the national tracking polls, which as of today are showing a much closer race, with some indicating that Romney has pulled into a narrow lead.   How much must Romney gain in the key swing states to overcome Obama’s polling lead? Using the RealClearPolitics state polling averages, Owen Witek created the following table showing the state of the race in the 12 closest state races as of today (Electoral College votes are in parentheses). The last column contains an estimate of the number of undecided voters in each state.

State

Obama

Romney

Obama Margin

Undecided

Michigan (16) 48.8 44.8 4.0 6.4
Ohio (18) 48 45.7 2.3 6.3
Pennsylvania (20) 49.5 44.8 4.7 5.7
Virginia (13) 46.8 48 -1.2 5.2
New Hampshire (4) 48.3 47.2 1.1 4.5
Colorado (9) 47.8 47.8 0 4.4
Iowa (6) 49 46.7 2.3 4.3
Florida (29) 47.1 48.9 -1.8 4
Wisconsin (10) 49.3 47 2.3 3.7
North Carolina (15) 46.5 50.3 -3.8 3.2
Nevada (6) 49.7 47.2 2.5 3.1

Source: Real Clear Politics, 10/27/12

Based on the RCP averages (and remember that Drew’s state-based polling formula includes a structural component and thus is different than the RCP simple averaging), Obama right now has 201 Electoral College votes in strong and lean states, compared to Romney’s 191. That leaves 146 electoral votes in the 11 swing states listed in the table still up for grabs.  How likely is it that Romney can pick up the additional 79 needed to reach 270?  If he holds his “lead” in Virginia, North Carolina and Florida, he picks up 57 more, leaving him with 22 to go. Assuming a small shift in voter sentiment, he might also squeak to victory in Colorado, earning another 9 electoral votes, leaving him 13 to go.

But here is where the math becomes difficult for Romney, and why Drew – as of today – believes Obama will hold on.  Obama leads by more than 2% in all the remaining battleground states.  His smallest lead is 2.3% in three states: Ohio, Iowa and Wisconsin.  Looking only at these three, Romney needs to win either Ohio, or Iowa and Wisconsin, to reach the 270 mark.   But, as Witek shows, there are not very many undecideds left in either Iowa or Wisconsin, so they would have to break strongly in Romney’s favor for him to eke out a victory in both states.  That means Ohio may still be Romney’s best path to victory, and that assumes Obama loses the other states – no sure thing.  Remember, Romney got perhaps a 2.7% boost from the first widely-watched debate that was generally viewed as a convincing win for him.   How likely is it that he will be able to almost match that total in the last 10 days among the much small number of undecideds in the absence of a similar focusing event?

Keep in mind that all these calculations are based on polls that are, by nature, very squishy, so we ought not treat the RCP averages as having more precision than they do.  In this respect, Drew’s model, which uses a different algorithm to analyze the polls and predict the final outcome in each state, presents a slightly different picture in the battleground states.  Here are Drew’ state-based calculations, complete with the 95% confidence interval.  (Note the cool color coding!). As you can see by the vertical line in the middle demarcating the 50% threshold, he projects that Obama will do slightly better in key states than a simple reading of the RCP polling averages might suggest.  In contrast to my simple RCP average, he has Florida, Virginia and Colorado all leaning toward Obama (although with a confidence interval that suggests Romney might be leading in all three states).  That means Romney has that much of a bigger hill to climb among the undecideds.

Of course, if Romney does begin to close the gap in the swing states, Drew’s model will pick that up, and it will adjust the forecast accordingly.   Regardless of the outcome, however, there is one overriding reason why you should be visiting his site for the next 10 days: in contrast to other forecasters (you know who I mean), Drew’s methodology is completely transparent.  Anyone can see and utilize his modeling equation, which he describes at length in this journal article  (which has been peer-reviewed and accepted for publication). Moreover, as an academic, Drew’s rooting interest in this race is to see whether his forecasting tool is validated. He has much less at stake if the model turns out to be wrong. If it is wrong, however, he can tell us why.  I call that progress.

P.S If you are coming to this site for the first time (there’s been a lot of traffic of late) I encourage you to follow me on Twitter at @MattDickinson44 – I tweet all new posts there.