Once again, Nate Silver proves he's a genius:
FiveThirtyEight: Politics Done Right
Obama's Share Determined Dems' Votes on ObamaCare
What was the single biggest determinant of whether a Democrat voted yea or nay on the health care bill yesterday? Actually, it isn't too hard to figure out:
This reflects the breakdown in the roll call based on the percentage of the vote that Barack Obama received in each congressional district in 2008. Members who are retiring from politics are excluded; those who are vacating their seats to run for statewide office are listed by the percentage of the vote that Obama received throughout the state, rather than their home district. Those technicalities aside, the trend is pretty clear. All 12 Democrats running in a place where Obama received less than 40 percent of the vote decided against the bill, whereas 195 of 202 running where he received a majority voted for it (including 64 of 64 in places where Obama had at least 70 percent of the vote). The swing votes tended to come from those districts in which Obama received less than 50, but greater than 40 percent of the vote two Novmebers ago. (Although it makes only the slightest bit of difference, the Obama vote share alone was a better predictor than PVI, which accounts for the results of the last two elections.)
FiveThirtyEight: Politics Done Right
