Chrystia Freeland's New Yorker piece about finance billionaires' loathing of Barack Obama is a fun read, and I enjoyed Felix Salmon's further analysis and elaboration, but I don't actually think there's a ton here that needs explaining.
Leaving finance and money out of it, if you think about American politics, you know that African-Americans, Hispanics, Asians, and Jews all back Democrats. You know that among white people, older people are more conservative than younger people and men are more conservative than women. So if you have a room full of older white men, then unless that room is full of Jewish men or gay men, it is overwhelmingly likely that they're going to be detractors of Democrats in general and Barack Obama in particular. If you get them all talking about politics, then a standard group polarization phenomenon is going to lead to some over-the-top statements and wild Hitler comparisons.
Obviously the financial regulation stuff, the tax stuff, the ins-and-outs of the crisis play some kind of role here. But there just isn't that much that really needs explaining.
For a comparison, suppose I went and hung out with a bunch of WNBA players and asked them about politics. What's going to happen? Well, I'll bet you anything that this disproportionately black, gay-friendly group of young women is not really enthusiastic about Mitt Romney. But it would be foolish to spend a lot of time on the hypothesis that their anti-Romney sentiments have some specific relationship to his ideas about women's basketball. The occupational structure of the American economy happens to have substantial overlaps with other politically salient aspects of America's demographics.