We have a similar kind of phenomenon in the UK with the older working class being staunch supporters of the Labour party despite it now actively hating them and supporting everything they complain about socially. For all of their lives, the Labour party has been the party of the 'working man', while the Conservatives have represented monied interests, and they can't break out of that dichotomy.

I think you reach a certain age where your beliefs have become so ossified it's impossible to change them, even if new evidence is staring you in the face. Cognitive dissonance produces a physiological pain response in the brain, so in some sense it is actually 'painful' for these people to reflect on their own beliefs and realise they might be wrong. It's easier to just disregard conflicting evidence entirely.