"When we suggest that our political behavior is driven largely by coalition loyalty, then, we’re not trying to single out political parties (Democrat, Republican) or political ideologies (liberal, conservative) as the fundamental focal points.
"Our hypothesis is that the political behavior of ordinary, individual citizens is often better explained as an attempt to signal loyalty to “our side” (whatever side that happens to be in a particular situation), rather than as a good-faith attempt to improve outcomes. In addition to the Do-Right’s motives, then, we also harbor the motives of the apparatchik: wanting to appear loyal to the groups around us.
"The desire to signal loyalty helps explain why we don’t always vote our self-interest (i.e., for the candidates and policies that would bring us, as individuals, the greatest benefit). Rather, we tend to vote for our groups’ interests.
"In this view, voting is seen as providing a psychological reward, like getting to “affirm one’s identity” or “feel a sense of belonging.”
"For an apparatchik, then, the real benefits come not from voting per se, but rather from all the activities surrounding the election, like attending rallies, discussing the issues, posting to social media, and watching election coverage with friends and family."
(From Hanson/Simler: "The Elephant in the Brain: Hidden Motives in Everyday Life"
Tribalism, pure and simple explains an awful lot of human behavior, including classism and political choices.
That really explains why so many people are so bad at explaining what they actually believe in and support, because they don't and they are just trying to conform to the policies of other people who have actually thought about it.