Yes sadly, right-wing Christians won't vote for someone who does not share their beliefs.
Most people would prefer someone with their beliefs. I don't see a problem with that.
Most Christians I know are delighted to have someone in the office now who shares their religious beliefs. But I believe almost all of them would vote for a conservative with shared values, Christian or no. But there would not be that extra sense of identification we have now. I believe much more important issues, as has been stated above, are issues like abortion, gay marriage and gun control (for some, not all). The religious questions is moot anyway if he, or she, doesn't share those values.
I am an active Mormon, but I don't feel Mitt is the guy we need in there right now. We NEED a fiscal conservative in there that will reduce the size of Government. That is not him. And his religion would truly be a liability at the National level. Remember when he almost unseated Teddy? The campaign was so negative, I think it set the high-water mark on campaign mudslinging.