In The Wall Street Journal, Juan Williams of Fox News and NPR writes about how race may factor into the election:
In a Wall Street Journal poll last month, 8% of white voters said outright that race is the most important factor when it comes to looking at these two candidates—a three percentage point increase since Mr. Obama claimed the Democratic nomination. An added 15% of white voters admit the candidates' race is a factor for them. Race is even more important to black voters: 20% say it is the top factor influencing their view of the candidates, and another 14% admit it is among the key factors that will determine their vote. All this contributes to the idea that the presidential contest will boil down to black guy versus white guy.
Consider also a recent Washington Post poll. Thirty percent of all voters admitted to racial prejudice, and more than a half of white voters categorized Mr. Obama as "risky" (two-thirds judged Mr. McCain the "safe" choice). Yet about 90% of whites said they would be "comfortable" with a black president. And about a third of white voters acknowledged they would not be "entirely comfortable" with an African-American president. Why the contradictory responses? My guess is that some whites are not telling the truth about their racial attitudes.
Williams concludes, "Mr. Obama needs to hammer home…conservative social values to capture undecided white voters. He might lose [Jesse] Jackson's vote. But he won't lose many black votes, and he will win the undecided white votes he needs to become America's first African-American president."
reason's Dave Weigel has done the dubious math on the idea that whites overplay their willingness to vote for black candidates to pollsters (variously called "the Bradley Effect" and "the Wilder effect"). Read about it here, here, and here.