With just over six months before Election Day, the 2012 presidential campaign looks dull but astonishing. It’s dull because Barack Obama no longer elicits the kind of passion he did in 2008, and Mitt Romney has never elicited much passion at all. But it’s astonishing because it features an African-American and a Mormon, two of the most discriminated-against groups in American history. In the year of Romney’s birth (1947) or Obama’s (1961), the idea that a presidential election would one day pit an American of Romney’s religion versus an American of Obama’s race would have boggled the mind.

When Obama first ran in 2008, Republicans wrestled with how to attack him without playing on antiblack bigotry. Now it’s the Democrats’ turn to be tempted. In the United States anti-Mormon bigotry has remained remarkably durable. According to Gallup, the percentage of Americans who say they would not vote for a Catholic, a woman, an African-American, or a Jew has dropped sharply since the 1960s and 1970s. The percentage saying they would not vote for a Mormon, however, hasn’t budged. In 1967, the first year Gallup asked the question, 17 percent of Americans said they would not back a Mormon candidate. When Gallup asked again last summer, the figure had risen to 22 percent.

Despite the media’s obsession with the alleged anti-Mormonism of evangelical Christians, the party with the larger anti-Mormon problem is the Democrats. According to Gallup, while only 18 percent of Republicans said they would oppose a Mormon candidate, among Democrats the figure was 27 percent. As if on cue, Montana’s Democratic governor, Brian Schweitzer, last week volunteered that women would not back Romney because his father was “born on a polygamy commune in Mexico.”

To its credit, the Obama campaign repudiated Schweitzer’s statement. But between now and Election Day, anti-Mormonism is going to be the Democratic Party’s constant temptation for one simple reason: there are votes in it.

The temptation comes in various forms. The first is to mock Mormonism for its allegedly weird theology. I recently heard a political commentator mock Mormons for the underpants some wear under their clothing. But undergarments designed to remind a person of his religious obligations are hardly unique to Mormonism. In truth, every religion’s practices and beliefs—if taken out of context—can seem nutty.

One reason Democrats may be more anti-Mormon than Republicans is that Democrats, on average, are more secular. Devout Protestants, Catholics, and Jews may be more tolerant of Mormonism because they understand from firsthand experience the comfort and strength that religious commitment brings. Many secular Democrats, by contrast, may start with the assumption that religious orthodoxy produces irrationality and intolerance. I don’t think, for instance, that there’s any way to understand the hostility that many liberals felt toward Joseph Lieberman in the 1990s—long before he became associated with the Iraq War and the John McCain campaign—without understanding their hostility to what they perceived as his moralistic Orthodox Judaism. Democrats may exhibit greater suspicion of Mormonism, in other words, because they exhibit greater suspicion of all organized religion. It’s just that anti-Mormonism is still socially acceptable enough to confess to a pollster.

The second way in which Democrats justify their anti-Mormonism is via the LDS Church’s own flirtation with bigotry. Until 1978 the Church of Latter-day Saints would not ordain men of African descent into the priesthood. And as recently as 2008, the church organized massively to ban gay marriage in California. It wouldn’t be surprising, therefore, if one reason Democrats are more anti-Mormon than Republicans is because African-Americans, gays, and lesbians are more anti-Mormon. But using the church’s historic (and even present-day) intolerance to justify intolerance toward its members is idiotic. LDS is hardly the only faith with a history of antiblack racism, and individual Mormons should be held no more responsible for the LDS Church’s antigay views than individual Catholics should be held responsible for the Vatican’s.

Democrats should remember the fear and revulsion they felt when conservatives played on Obama’s race and do everything humanly possible to prevent their party mates from doing the same. It’s important that Barack Obama wins this election, but for the country’s sake, it’s important that Mormonism not lose.