I think that it's great to believe in something. Having a political belief is very worthwhile. Please don't plaster it all over my Facebook page!
This is simply my opinion, but, I joined the social network to keep up with current and old friends. I really don't give a rat's rear end who you're voting for. It's a secret ballot, lets keep it that way. If you are my Facebook friend, there is a reason for it. If you bully my beliefs, you're gone. If you really support a candidate...send his/her campaign some money. Otherwise you run the risk of becoming a social bore. I feel that I can tell you this, right? After all, we're Facebook Friends!