I don't think there is any Republican who can carry Mass. in a national election. I don't get the problem with his faith. I have had friends over the years who were Mormons and they were great people, very family oriented, hard working and trustworthy, and deeply patriotic.
The problem will be with the media, who keeps pushing the nut-case LDS fringe group with all of the underage "wives" as if this is a legitimate branch of Mormonism. I expect he will get a grilling on several shows about his beliefs. (This will be because he is a Republican. Democrats can worship the Wizzle-bird of Locoland and not one reporter will even ask a mildly interested question.)
Got my work done. New bed with tulips, lavender, and daylilies all planted and mulched. Tranasplanted some other daylilies and planted a couple of bargain hosta. Whew!
See my post # 737, carrying Mass may be less important than making all of New England competitive.
I bet that the dims will try to "smear" Romney as a Mormon, perhaps with that polygamist guy, and it will get ugly, but it will end up hurting them more than him.
Contrary to their belief system, Americans are not bigots.