"From Romney's perspective, voters who had moderate contact with Mormons were more of a problem than voters who had no contact with Mormons at all," write authors Quin Monson of BYU, David Campbell of Notre Dame and John Green of the University of Akron.
Multiple polls have shown a swath of Americans, especially those who align with an evangelical faith, are wary of voting for a member of The Church of Jesus Christ of Latter-day Saints. Some faiths view Mormons as outside the Christian fold.
The study, published Tuesday in the journal Political Behavior, calls the potential hurdle of religion faced by Romney, and previously by the first Catholic president, John F. Kennedy, as a "stained glass ceiling," one that's yet to be broken by a Mormon.
The professors say their research confirms the theory of social contact in that a person familiar with someone from a certain group views that group more favorably. Their academic look at the faith hurdle included 2008 polling of different groups of Americans, each with various information, including some with just a biographical sketch of Romney and some with critical but true information about LDS adherents, such as the fact that some faiths don't view Mormons as Christian.
For those who know a Mormon well, the critical information didn't affect their opinion of Romney. For those with a passing relationship with a Mormon, it mattered.
Campbell, an associate professor of political science and director of Notre Dame's Center for the Study of American Democracy, says having a close relationship with a Mormon tends to allow a person to brush off concerns more.
"Mormons are distinctive; there's no question about that," Campbell said Tuesday in an interview. "If you know a Mormon in passing, all you know is the distinctive part and you haven't developed that relationship in order to put that distinctiveness in a wider context of someone you know well or someone you love."
Romney's campaign declined comment on the study.
A Salt Lake Tribune national survey in 2011 showed that a large majority of Republicans were comfortable voting for a Mormon, though 14 percent remained uncomfortable. Slightly fewer independents, about 61 percent, said they were comfortable with backing a Mormon for president, while some 27 percent were uncomfortable. Less than a majority of Democrats 46 percent said they would be comfortable voting for a Mormon for president and 36 percent said they would be uncomfortable.
Polygamy was the most cited reason for those who had reservations, though the LDS Church ended the practice more than a century ago.
There was a bright spot in the survey released Tuesday, according to the professors who put it together: While the short-term prospects for politically small and socially-isolated faiths, like Mormons, may be "worrisome," the medium-to-long-term prospects are far brighter.
The more Americans who get to know someone of such faiths well, the better outlook for their acceptance by voters as in what happened with the Catholic Church or Judaism.
"Should Mormons or Muslims, Buddhists, Sikhs, or any other group follow the same pattern, we would expect them to experience that same degree of acceptance, and shatter the stained glass ceiling once and for all," they write.