i'm sure that the internet just imploded.
listen - he's the only blackish looking candidate i know of, ever, that made sure to tell everybody he was half white, every time he spoke. generally, black politicians run as being black, and embrace their blackness, and make it a part of their campaign. obama didn't do that - he ran as biracial, and put it at the very front of his messaging.
so, at the least, it's an apples and oranges comparison, because he really wasn't like somebody like jesse jackson, who was 130% black and wouldn't go five minutes without asserting it.
a lot was written about obama being a blank slate - voters projected what they wanted on to him. so, he was a socialist, if you wanted him to be, and a conservative if you wanted that, too - or he was what you most feared, if you leaned towards the opposing team.
i don't think it's such a stretch to think that a substantive number of white voters took his arguments for post-racialism, and his biography as growing up the son of a white woman from kansas, the way they wanted to, and projected an essentially white image of him.
you can agree with me or not, but i think it should be acknowledged, at least, that obama was different than virtually any other black politician in terms of his identity, and it makes a great deal of sense to tie things like an absence of the bradley effect to that rather clear matter-of-fact.