The problem with stage magic is that no matter how impossible and amazing it looks, It's still just a stage trick. If this magician brought this magic into the real world and disappeared an evil dictator with the snap of his fingers people WOULD believe him. He'd have worshipers immediately.
There's was an opinion article in the NY times a while ago written by a professor at Princeton. It wasn't really about magic but it dealt with how people remember things and when presented with a false statement along side a disclaimer that it is in fact false they can recall it later as being true, having forgotten the disclaimer. It goes on to talk about how people are more likely to remember things that fit in with their world view.. Actually instead of talking about it I'm just going to link it.
HERE!
As for religion, I think people are looking for answers. They see their lives and they shrug and ask "Is this it?" I think many people would just breakdown completely if the only answer they could find is "yeah.. This is all there is..." As for republicans, I have no fucking idea.