If something can't go on forever, it will eventually stop. That applies to any system that gives stupid people the same political voice as the rest of the electorate. I mean, it seems kind of obvious, doesn't it?
(it's not the working class)
Answer: because they're stupid.
The ones who weren't stupid were impossible to herd to the polls, or at least a lot more difficult. As a result they were outnumbered. Any system that removes the influences you cite will leave the same stupid voters in place, ready to fall for the next con man who comes along.
The problem isn't the money. The problem is the power. I'm tired of giving stupid people so much power over my life.