It probably depends upon the Mormon in question.
A lot of people, for instance, did support Romney, and may get a chance to support him again in 2012.
I'd be just as apt to vote for a Mormon as for a Southern Baptist like George Bush, or any other type of Christian, or an observant Jew.
I see their religious ideologies as being equally weird, but there's really no getting away from electing a member of some major religious faith, since openly nonreligious candidates really aren't on the ballots, for obvious reasons. We still live in a very religious society.
I try to go with candidates that appear to be only moderately religious, or better yet only nominally religious, or at the very least candidates who don't let their belief in magical invisible deities in the sky influence their foreign and domestic policy overmuch.
I greatly prefer leaders such as Barack Obama, who appear to believe strongly in religion as a social force for unity, charity, and goodwill (for those who need an outside motivation in order to exhibit these positive qualities, which seems to be most people) without displaying any real interest at all in the more fanciful and/or oppressive elements of their chosen religion.