Jay Cost looks to November:
The best case scenario for Democrats at this point is a nominal majority where the median member is not a terribly reliable ally of the party's liberal leadership. Something similar is set to occur in the Senate, where a Republican gain of at least five seats will push the filibuster to more conservative ground, from Brown/Collins/Snowe to Alexander/Cochran/Murkowski. Barack Obama ran for and won the Presidency in 2008 based upon a pledge to pursue bipartisanship, and the results in 2010 are effectively going to force him to do just that, at long last.
Not just him.
2006-2011 archives for The Daily Dish, featuring Andrew Sullivan