The reasons seem pretty obvious:
The party-buckers on the 220-215 vote on Saturday night included 39 Democrats who voted against the bill. Of them, 31 represent districts that voted for John McCain over Barack Obama. Republicans are targeting many of them for defeat in the 2010 election. Of the other eight, three are serving their first terms in districts in which they defeated or succeeded Republicans in the 2008 election.
This article available online at:
http://www.theatlantic.com/daily-dish/archive/2009/11/the-dems-who-punted/194304/
