Mr. Huckabee of Arkansas has now advertised himself in Iowa as the "Christian" candidate, and he wants people to vote for him because he has a "Christian" identity. Based on his earlier remarks about Mitt Romney, it is clear that he is saying that the other candidates--and especially Romney--are not as "Christian" as he is. Huckabee is asking Iowans to elect a Pastor-in-Chief.
With his ad campaigning on the basis of being a Baptist minister, where does Huckabee go in the general election? Evangelicals are not a majority of America, and making it the key part of his identity could get Catholics remembering why they used to be mainly Democrats.
And here’s another point: Mormons are not a big percentage of voters, but they are a major part of several states in the West. I am pretty sure that Huckabee as the white knight of Christianity is going to come across to them as just one more professional Mormon basher, remembering the hatchet job the Baptists did on Mormon beliefs when they had their convention in Salt Lake a decade ago. As a result, a lot of Mormons are going to sit out the election, vote for a third party candidate, and others will vote for even Hillary Clinton out of disgust or even fear of government persecution from a Baptist preacher at the helm of the government–they had their fill of that back when the Radical Republicans ran the government and took away Mormon rights to vote. Clinton demonstrated his disregard for Utah when he created the huge Escalante-Grand Staircase National Monument even while lying about it to the governor and the Utah congressional delegation. There are many other ways a president has discretion to injure a state he doesn't like, like closing a military base. As a result, Utah, Idaho, Nevada, Arizona, and Colorado could, by a plurality (and winner take all of their electoral votes), go for the Democratic candidate. And that, all by itself, would be enough to lose the election.
If Huckabee is nominated, is he going to make the traditional visit to the LDS Church president in Salt Lake? Huckabee might feel like trying to make nice to the Mormons, but on the other hand, the same people who told him to make religion an issue in the Iowa caucuses might say that he’s going to be betraying his base if he visits Salt Lake. And if he does ignore the Mormons, the opposition to him personally is going to solidify. If he gets only a little Mormon money, or campaigning, or voting, it will turn several states from Red to Blue. And there are going to be other people who react to Huckabee the Crusader the same way that others react to Mitt the Mormon. They don’t want the Southern Baptist Convention controlling the White House.
I think Huckabee has taken the “America is a Christian nation” thing too seriously. He thinks the US is his brand of Christian, rather than being a Catholic-Baptist-Episcopalian-Lutheran-Mormon kind of Christian.
Back when Genghis Khan ruled China and more of the world, he used a lot of foreigners as advisors and government administrators, because they had no political base that they could use to threaten him. For the same reason, electing Romney would be a way for Americans to ensure that he is responsive to all of them, since he has no large political base of his own. On the other hand, if Huckabee is elected, he would feel a primary loyalty to his own brand of Christian, that would in fact take priority over his debt to Catholics or Mormons or anyone else. The Christian Right has pressed George Bush to be loyal to it as his base of support, but that is nothing compared to the pressure that will be on Huckabee to live up to the expectation that he will rule as an explicit Baptist.
The foreign policy consequences of that will be interesting, but I doubt they will be positive. Osama bin Laden will take it as a propaganda point: America is being run by a Baptist minister who has declared that is his core identity, the president is on a crusade, and all Muslims must oppose it by defensive jihad. And what will Huckabee do when Evangelicals appeal for him to help their missionaries who try to be active in Muslim countries where they are not legally invited to preach?
Huckabee is trying to differentiate himself in the market, and has chosen his brand identity.
I think for Romney, this may create both the need and the opportunity to give a speech about religious tolerance and pluralism in America. Romney can now brand himself as the candidate of tolerance for diversity and freedom of speech and thought. He can point to the Christians who put Article VI in the Constitution and created the First Amendment and declare that he is that kind of Christian. A Christian who seeks common ground with all Americans rather than to exclude them from political salvation.