Somehow I missed this tidbit in the Pew poll released a couple of months ago: Black people see Obama as "black," while white people see him as "mixed":
A poll is a crude instrument for detecting this kind of nuance, but it's pretty traditional for black folks to identify people of mixed parentage as "black." It's a matter of race and history: After all, being mostly white didn't get Homer Plessy the seat he wanted on that train. My view is that self-identification is the most important criteria, but the president obviously doesn't see a conflict with identifying as a "mutt" and being a black man. Most biracial adults I know, including myself, don't either.Overall, about a quarter of Americans (27%) see President Barack Obama as black; a 52% majority see him as of mixed race. But the latest Pew Research Center racial attitudes survey finds views differ sharply among racial and ethnic groups. Offered a choice, most blacks (55%) say Obama is black, while about a third (34%) say he is mixed race. Among whites, the pattern is reversed.
I don't really have any complex theories for the difference, except to say that I think it's probably easier for some people to relate to the president if they think of him as somehow "like them," and I think this basically applies to everyone. That's not to say that's the only reason you might identify Obama as mixed--noting the president's biracial heritage seems to be a common tactic among people who strongly dislike him, as though they expect their audience to find miscegenation offensive.