Some people simply don't like him. I don't know why, exactly, because frankly I think he's the best candidate remaining, by far. But suffice it to say that they have their reasons, even if the most adamant of the anti-Obamas in this thread have had an unfounded basis for it.
Still, it's just like how you and I support Obama but not Clinton. We have our reasons; they find them to be bullshit. The anti-Obama pro-Clintons have their reasons; we find them to be bullshit. But what sets people like HazelGod and myself apart from your cut of the ilk, is that we understand that they've justified their reasoning amongst themselves, far beyond issues of race.