Romney has a problem and it is not healthcare reform. Romney is a Mormon.
The Constitution is clear that there will be no religious test but that has to do with the governing entities of our nation and not the citizens. We are free to apply a religious test to our vote. Kennedy knew that back in 1960 when he faced down Protestants who were wary of a Catholic being elected and taking its orders from the Holy See (at least Salt Lake City is American). His speech was a forceful defense of American secular government. He went on to win the presidency.
Faced with a religious test in 2008 during the Republican Primary, Romney took a different approach. He did not defend American secular governing institutions. In that speech, he said this: "Freedom requires religion just as religion requires freedom."
Obviously, he has no problem with a religious test. He just wanted Mormons to pass. He failed. Mormons did not pass the religious test placed on Republican candidates.
So now he is back (possibly, along with Huntsman) to see if a Mormon can be president. Personally, I don't think he can do it. The Faustian Bargain that the Republicans have made with politicized Christians will not allow it.