Obama was never guaranteed the black vote. Polls weren't giving Obama 90 percent of the black vote in January - he only started getting these levels of support when it looked like he might have a chance to win. Al Sharpton never got as high a percentage of the black primary vote. Neither did Doug Wilder or Carol Mosley Braun. Obama's done better with both white voters and black voters than any (partly) black candidate in Democratic history.

Then the Clintons started dismissing the black vote and here we are. You know of non-white candidates that win elections by disenfranchising white voters?