The White Vote in 2010

There are currently 72 House districts in which whites make up less than 60 percent of the population. Democrats hold 70 of them. Nearly all of these districts will keep going Democratic regardless of national trends. Control of the House hinges on the 363 mostly-white districts.

Democrats thus have reason to worry, as Michael Barone noted last month, and as Chris Cillizza reports in The Washington Post (h/t Fred Lynch):

"Since in the past House elections white voters tended to represent the independent vote, [the midterms] will surely be devastating for Democrats running in an election that will be a referendum on the Obama agenda," predicted one senior Democratic operative who closely tracks House races.

In Washington Post-ABC polling, Obama's approval rating among white voters has dropped from better than 60 percent to just above 40 percent. In a June poll, 46 percent of white voters under age 40 approved of how Obama was doing, compared with just 39 percent of whites 65 and older.

The latest NBC-Wall Street Journal poll reveals that Obama's standing among white voters is remarkably similar to that of President George W. Bush at this same time two years ago.

In the June 2008 NBC-WSJ survey, 37 percent of white men and 26 percent of white women approved of the job Bush was doing. In the June 2010 poll, an identical 37 percent of white men approved of Obama's handling of his job, as did 35 percent of white women.

...

One senior strategist, speaking candidly about his concerns on the condition of anonymity, noted that white voters made up 79 percent of the 2006 midterm electorate, while they made up 74 percent of the 2008 vote. If the white percentage returns to its 2006 level, that means there will be 3 million more white voters than if it stayed at its 2008 levels. That scenario, said the source, "would generate massive losses" for House and Senate Democrats in November because of Obama's standing with that demographic.