Romney

I don't think Romney's Mormonism would have any more effect on his Presidential performance than Bill Clinton's Baptist affiliation had on his. So the fact that Romney is a Mormon is not much of an issue in that sense.

But my friend Tim observes that having a Mormon President would give Mormonism a boost in the mainstream respectability department that I'd be sad to see it get.

On the other hand, the light has nothing to fear from darkness. A presidential light on Mormonism might expose more clearly its deep heresies and problems. Such as Joseph Smith's "translation" of Egyptian hierglyphics in "A Pearl of Great Price" that have been shown to be completely wrong since after Smith wrote, archaeologists learned how to actually translate hieroglyphics.