class or race?

[All Along The Watchtower]

Depends on what you mean by "class." Income and wealth is generally positively correlated with voting Republican (and has been for a long time), but post-graduate educational attainment is increasingly correlated with voting Democratic. There's also the matter of religiosity (or lack thereof), regional divides, local divides between metropolitan and rural areas, etc.

Also, there's a general difference between the parties, even among those of the same social class, in the kind of work people do, and the industries they are involved in.

As far as race goes...the Democrats are more racially diverse than the Republicans, but IIRC, are also majority-white. Goes to show that the American political spectrum is still whiter (and wealthier!) than the population as a whole.