Why did some seemingly smart people vote for Obama?

I've been puzzling over the fact that a lot of seemingly fairly intelligent, reasonably well-off Americans seem to have voted for Obama, despite his almost-blank resume, his seeming devotion for many years to the bigoted Jeremiah Wright, his membership in the New Socialist Party and so on.

Were a million or so Americans with IQs above 120 simply unable to see that the guy was determined to push through programs that would likely destroy the country? Or did they just "drink the KoolAid" and literally not have any idea of the guy's background?

I really can't believe that anyone who knew what Obama's views really were, and the types of programs he promised to enact; was smart enough to know these would likely do great harm to our country would still vote for the guy anyway. Even as cynical as I am about leftists, I can't believe anyone raised in this country in reasonably comfortable circumstances could want to harm it.

So that leaves one of the first two options.

And I think commenter Fat Man at Vanderleun's American Digest nailed it:

A lot of Obama voters have high IQs. [But] they used their intelligence to convince themselves that [Obama] was something he never was.... Their intelligence enabled them to ignore... the available evidence. [and to convince themselves that the fact] that he was a hard left Chicago politician of limited abilities and no executive experience, who did not understand or even like the USA -- was irrelevant.