As a Mormon who did his missionary work in France, Mitt Romney knows something of uphill battles. Imagine spreading a faith that renounces smoking, coffee and alcohol in the cafes of Paris.

Romney’s current task may seem easy in comparison. But his religious beliefs remain an obstacle. About 20 percent of Republicans and 23 percent of Protestants tell Gallup they would not support a Mormon for president. A portion of conservative Christianity is unhinged in its condemnation, regarding Mormonism as a dangerous, secretive cult. Even without recourse to calumny, it is clear that evangelicals will not be reconciled to Mormon doctrines without ceasing to be evangelicals.

Yet Romney’s faith should not matter. Presidents are elected for their policy views, leadership skills and character, not their soteriology. Such theological convictions about salvation may be infinitely important, but they are politically irrelevant. The whole “no religious test for office” idea remains a good one.

But presidential primaries are not always the best place to maintain such distinctions. In interfaith relations, it is the lack of familiarity that breeds contempt — and portions of America still view Mormonism as a threatening novelty. The last time Romney ran in South Carolina, he was greeted by anonymous fliers attacking his faith. Anti-Mormon attitudes could make a difference in some states, particularly in close races.

Among conservatives, however, this opposition is more likely to fade than build. No primary opponent of Romney’s can exploit these sentiments, at least in an overt way. When Mike Huckabee tried during the last election, he was forced to make a very public apology. The Church of Jesus Christ of Latter-day Saints is America’s fourth-largest denomination; Mormons are one of the nation’s strongest conservative voting blocks. A serious Republican candidate simply can’t run an anti-Mormon campaign.

As political choices in the primaries become less theoretical, Romney is likely to benefit. The question posed to religious conservatives will no longer be: “Would you support a Mormon for president?” If Romney’s campaign is effective, the question will be: “Would you support a conservative Mormon who can beat a liberal next November?”

Since their political reemergence in the 1970s, conservative evangelicals have lived with a tension. They hold tightly to their theological convictions. But there isn’t a conservative evangelical majority in America. This mathematical reality is what led Jerry Falwell to associate politically with Pentecostals and Catholics, as well as with Jews and Mormons. Such ecumenism has been an unexpected contribution of the religious right. In a democracy, the desire for influence tends to overwhelm theological differences. If Romney looks like the likely nominee, mainstream religious conservatives are more likely to build bridges than torch them.

But even though conservative objections to Romney’s Mormonism are likely to diminish, criticism by secular liberals is likely to blossom.

On politics, Mormon church authorities have generally kept their heads down over the past few decades. Past interactions with the federal government were unpleasant — President James Buchanan, for example, once sent about a third of the U.S. Army to suppress a rumored Mormon revolt in Utah. Mormonism has understandably developed a tradition of non-interference in political matters.

But in 2008 Mormon leaders raised their heads in support of Proposition 8 — the California initiative against gay marriage. Their commitment to the traditional family runs deep, and no issue is currently more likely to provoke liberal ire. Secular progressives will add this transgression to a history of Mormon offenses against women and minorities and raise, as usual, the specter of theocracy.

Recent Mormon involvement in presidential politics does little to justify these fears. Morris Udall and George Romney were hardly religious radicals. Mitt Romney and Jon Huntsman are, by most measures, the moderates in the current field.

Yet secular tolerance for the emphatic faiths has been thinning for some time. To many liberal thinkers, conservative religion is inherently illiberal. Mormonism only magnifies those concerns. Damon Linker has warned that Mormon leaders, claiming prophetic authority, might dictate to an American president. Jacob Weisberg has insisted, “I wouldn’t vote for someone who truly believed in the founding whoppers of Mormonism.” Twenty-seven percent of Democrats currently say they would not vote for a Mormon — a higher percentage than among Republicans or Protestants.

Will Romney’s Mormonism matter? It depends. On much of the right, politics will eventually trump theology. On at least some of the left, secularism will trump tolerance.

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