I talked with my wife about this a few days ago. Education and economic issues have a huge influence on this.

If you have issues with the huge complexity of the world around you (because of functional illiteracy) or cannot spend some time to form your own opinions (because of economical insecurity and long hours, kids make it even harder), you don't have the capacity to engage with messsages more complex than "immigrants bad" or "Eggs expensive" - stuff that you process emotionally, not intellectually.

I think that's what made Obama's campaign so powerful - everything boiled down to the simple one word message "Change".