Let’s take a trip back in time to June 2011, when Sarah Palin and Donald Trump were still battling for the GOP nomination.

Here’s how people felt about voting for various minorities back then:

Only gay people and atheists were more widely distrusted than Mormons. There seems to be a solid fifth of the country who seriously dislikes Mormons for some reason. It’s been that way for a very long time.

See?

It’s pretty easy to come up with a list of people who generally dislike gay people and atheists, but who makes up the chunk of the population that consistently opposes Mormons for president?

Just about one fifth of everybody finds Mormons unfit to lead. Only education level and party affiliation have a real effect on approval rates.

So what explains the uniformity of the numbers across all of these demographics? Here are possible two explanations.

1. There is a sizable chunk of the population that is uninformed about Mormonism, and their views are determined by their limited exposure to the religion.

According to this theory of the Anti-Mormon Bloc, voters oppose a generic Mormon candidate because of their incorrect assumptions about the impact of such a candidate’s religion on his ability to perform his presidential duties. These voters may believe that the Church of Latter-day Saints would exert too much influence on a Mormon president, for example.

In 1960, 25% of American voters said they would not vote for a Catholic candidate for president. John Kennedy was opposed from the religious right by those who feared that his loyalties would lie with the Vatican and from the more secular left by those who believed that his Catholicism would unduly influence his policy-making in office.

By 1962, when neither group’s suspicions had been confirmed, the number of voters who would never vote for a Catholic had been cut in half.

The Catholic president turned out to be a lot like a Protestant president. It’s possible that those folks who currently say that they would not be comfortable with a Mormon president have some unfounded presuppositions about the loyalties and motivations of Mormons that would ultimately prove untrue.

If this is the case, Anti-Mormon sentiment would likely fall sharply during a Romney administration and Mormonism would enter the political mainstream.

2. There is a sizable chunk of the population that is very informed about Mormonism and is kind of weirded out by it.

Catholicism, for all its detractors, is much more mainstream than Mormonism. In fact, Catholicism is the mainstream when you really think about it.

An alternative explanation for the Anti-Mormon Bloc is that some people know too much about Mormonism. There’s some weird stuff in there.

Here’s a brief roundup from an article that appeared in Slate last fall:

The founder of the church, one Joseph Smith, was a fraud and conjurer well known to the authorities of upstate New York. He claimed to have been shown some gold plates on which a new revelation was inscribed in no known language. He then qualified as the sole translator of this language.

[...]

On his later forays into the chartless wilderness, there to play the role of Moses to his followers (who were permitted and even encouraged in plural marriage, so as to go forth and mass-produce little Mormons), Smith also announced that he wanted to be known as the Prophet Muhammad of North America, with the fearsome slogan: “Either al-Koran or the Sword.” He levied war against his fellow citizens, and against the federal government. One might have thought that this alone would raise some eyebrows down at the local Baptist Church.

[...]

Saddling itself with some pro-slavery views at the time of the Civil War, and also with a “bible” of its own that referred to black people as a special but inferior creation, the Mormon Church did not admit black Americans to the priesthood until 1978, which is late enough—in point of the sincerity of the “revelation” they had to undergo—to cast serious doubt on the sincerity of their change of heart.

[...]

More recently, and very weirdly, the Mormons have been caught amassing great archives of the dead, and regularly “praying them in” as adherents of the LDS, so as to retrospectively “baptize” everybody as a convert.

Some have concerns about the influence of the Church of the Latter-day Saints in a Mormon administration.

*   *   *

In truth, the Anti-Mormon Bloc is probably made up of people who fit into both categories. I don’t think Mitt Romney’s religion will have much of an impact on the outcome of the election in November, though.

John Kennedy faced similar levels of societal opposition, but it was his contacts in Chicago that swayed the outcome of the 1960 election, not his Catholicism.

Romney’s done a good job of deflecting questions of religion to this point, and I expect him to continue doing so. That is not to say his religion won’t be an issue, however.

There are troubling aspects of Mormonism, including the activism of the church and the weird post-mortem baptisms, that Mitt Romney should have to address.

A candidates’s religion shouldn’t matter, of course, but it always does.

Only gay people and atheists are more widely distrusted than Mormons.

A solid fifth of the country seriously says they would not vote for a Mormon, and it’s been that way for a very long time.

Here’s a few guesses as to why.