THE BLOG
03/19/2010 01:28 pm ET Updated May 25, 2011

HCR Vote Probabilities For the Undecided

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The "undecided" health care votes are mostly right where you'd expect: marginal Dem districts and among the more moderate House Democrats. There are a few outliers that may be real or may be temporary hesitations, and there are a few surprises in both directions with firm yes votes in questionable districts and puzzling no votes (though the Stupak amendment and abortion account for some of these.)
Who's up in the air, and what are their probabilities of voting no? I model this based on Obama's share of the two party vote in the district in 2008 and the member's roll call record on a liberal-conservative scale as estimated by Simon Jackman of Stanford University (Thanks!).  Other variables don't add to the model: being in trouble for re-election doesn't add anything over and above the district and ideology measures. Those in trouble are in districts you'd expect to be trouble. Retirement and seeking higher office also have no measurable effect. And the Washington Post whip feature provides health industry contributions and percent uninsured in the district. Those do nothing to explain position either.  In the end, when you are down to a game of inches like this, the statistical model can only speak to the broad tendencies, not the special circumstances that may flip a member on way or another.
These positions are taken from the Washington Post and The Hill's published counts. They were updated through noon on Friday, though positions are certain to change. 
First, the members who voted No on November 7 and who are currently undecided, with their estimated probability of voting no now.
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Now the much more numerous "Yes"votes in November, who haven't taken a firm position this time:
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And for some perspective, how these probabilities vary by lib-con roll call records (via Simon Jackman), and then by Obama vote in the district.
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Based on the probabilities alone, the Speaker and White House still have some heavy lifting to do, despite the sense that the Democratic members are shifting towards a very narrow passage.