I think this exit poll result is even more striking than the one about the age composition of the electorate:
Now the median American household makes $50,222 so this vote split should generate a pretty even division of the electorate. But 63 percent of voters came from households with above-average incomes. In part that’s because two-adult households are more common in the above-average bracket, in part that’s because non-voting non-citizens are more common in the below-average bracket, and in part it’s because high-income people turn out at higher rates.
This not only partially explains the election results, it shapes the larger political climate. You can’t win an election on the basis of the votes of children and immigrants. You need actual voters. And the median voter is quite a bit richer than the median person over and above all the other ways in which higher income people have more political influence.