Ridiculous. Look at the actual exit polls over the years up to the 2000 elections ( the 2002 exit polls were botched so no solid data) at http://members.cox.net/fweil/ExitPolls7200.html
The numbers don't break out by income crossed with race, but there aren't enough blacks to cancel the fact that those making less than $15,000 per year went 57% for Gore, while those making over $75,000 went 53% for Bush. At worst, the white working class is divided between the parties, while the white elite goes overwhelmingly for the GOP, given the fact that rich blacks and Jews vote Dem understate the general white elite GOP voting patterns.
And if you want to explain the professional tick towards the Dems, it's all about gender. There is relatively little difference in voting patterns between the sexes among less educated folks, but once you hit college graduates, the gender gap is a frigging chasm.
Male college graduates voted for Bush 57% to 39%, while female college graduates went for Gore 57% to 40%. More specifically, men vote Republican with greater frequency as they attain more education, while college educated women vote Democratic more than their less educated sisters. It is only because abortion and other gender-based issues make "class" more problematic for women that we do not have a more strict class-based voting system.
Generally, the GOP gets the votes of religious white married men and women, along with wealthy non-religious men. The Dems get the votes of blacks, latinos, unionized and low-income white workers of both sexes and professional women.
And that's pretty much the coalition politics the progressive movement has wanted. If progressive Dems were willing to be more agnostic on abortion and other "social issues", we could probably trade the votes of professional white women for more white religious working class men and women.
But dismissing the Dems generally as the party of white professionals, when professional men vote overwhelmingly Republican, shows a blindness to gender issues involved that is astounding.
Nathan Newman