Pondering casually just how many people I know personally who share my beliefs are poor or rich, it seems to me most of them are doing well enough, and I can count some doing quite well, such as business owners, lawyers and doctors. Don't have statistics at hand of course, and I can think of some poor ones too, mostly single mothers. I don't know everybody's politics though. Not sure where you are getting your statistics.
As nwr suggested, political beliefs simply reflect different views of what makes for the best society.
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