Election 2010 was a vote to repudiate the president's policies.
But if it's true, Democrats who voted against the president's policies should have won more than the general caucus. Democrats who voted with the president should have lost more.
The stats muddy the punditry. Of the 33 House Democrats who voted against health care reform and ran in 2010, why did 21 lose their re-election bids* -- a worse reelection rate than the 56% Republican House victory? Of the 42 House Dems who voted against climate change, why did 25 lose -- again, a worse reelection rate than the national average? And of the Senate Democrats who voted for both the stimulus and health care and ran in November, how did all but two win?**
The answer is voter demographics. Many conservative House Democrats lost reelection for the same reason they voted against health care and climate change. They held down conservative districts that Obama painted with a thin layer of blue when he won in 2008. Many liberal Democrats won reelection for the same reason they felt safe voting for health care and climate change reform. They represented deep blue electorates.