McCain himself doesn't strike me as a particularly intelligent person, just from the way he talks, reading his facial expressions during the debates, mannerisms, etc... I also lean towards believing that people whom attribute various aspects of diplomacy and politics (or anything, for that matter) to God to not be all there in the head, which given our current national situation, isn't something I would feel terribly comfortable with. Obama, while attending church and saying he is Christian, doesn't seem to do this. In my opinion, I don't even think Obama is a Christian. He is probably an Athiest (or at least Agnostic), but if this were to become known, there wouldn't be a chance in Hell that he would become President (look at what happened to Romney, and he still at least believed in God).
All this being said, I have no room to talk. I am not even registered to vote. :-)