Scientologist: Definitely no, they are a psychotic fringe cult who's beliefs would sound dumb to a 5 year old.
Muslim: Probably not. It is likely dumb of me, but I can't say I particularly like or trust Islam at the moment.
Mormon: If he is a fringe polygamist, no, but if he is an average Mormon, I would vote for him, if his political views are similar to mine.
Pagan: I assume this is the new age/wicca/nature worshiping form of paganism we are talking about here, so probably not, for the simple reason I do not regard this as a religion. It is nothing more than a collection of superstitions with some PC crap thrown in. I also have a hard time believing that they actually believe it.
Hindu: I think Hinduism is a form of Paganism, but it is not a bunch of weird new age drivel, and it is large and established enough to count as a religion in it's own right, so I would base my vote on his politics.
Catholic: Maybe, it depends on his politics.