I think no one really knows what the different parties represent any more. Most people I know voted Republican were low-wage working people, where my highly paid educated friends voted Democrat. Isn't it supposed to be other way around? No wonder everyone is confused.
It’s pretty obvious from election maps and donor data that the democrats are now the party of coastal/urban elites, despite what they may advertise.
I'm from flyover country, one of those three states that went Biden this year surrounded by a sea of red. You know, one of the three states that elected half the members of 'the squad'. Sure, California rich people can throw in a lot of money, but that's true for both Republican and Democratic parties. Don't dismiss our importance in the Democratic party. We turn up & do the work, including the work of talking with our 'red' neighbors and actually trying to work things out in this country.
As for high & low vs middle, it just doesn't make sense to me. Lots of rich people supporting the Republicans -- lots, lots, lots. Lots of rich people supporting the Dems. Poor people split by race and geography. Middle class people split by race and geography. The split by geography and race is more significant than the split by income, in almost every presentation of data that I see.