Do you believe that external factors, more than policy debate, play a larger role in the president’s ability to pass legislation? For example, President Bush was able to do more after 9/11, but later on, when Iraq deteriorated, he could not pass immigration or Social Security reform. If this is true, why should voters move on from healthcare failure and place trust in a president that cannot solve the troubles of more than 45 million uninsured Americans?

I should be clear that I expect some negative fallout for Obama and Democrats if health care fails to pass. Most noticeably, they will likely take a hit in the polls, (although as you show the ratings for Congress as a whole can’t drop much more.) And of course he’ll get skewered by pundits. I remain skeptical, however, that this will translate into a significantly weaker presidency as measured by his ability (already weak by virtue of the institution) to get other legislation through Congress. I think there is a tendency to overestimate the linkage between one issue and another; typically each are debated on their own merits, and within their own political context.

Of greater concern, I would think, is the potential fallout of the failure to pass legislation on the Democrats’ chances in the 2010 midterms – but even here I think the impact is marginal and dwarfed by the problems posed by a sluggish economy.