According to the study, members of The Church of Jesus Christ of Latter-day Saints unequivocally reject polygamy — only 2 percent said the practice is morally acceptable.

Editor's note: This article is the fifth in a five-part series examining survey findings on Mormons in America. Read the first, second, third and fourth articles here.

David Letterman knows how to get a laugh.

Like most comics, he riffs on the day's news, deadpans the camera and revels in audacity.

"Oh, did you hear about this?" the host of CBS' Late Show with David Letterman asked his audience recently. "A campaign staffer on the Newt Gingrich campaign was fired because he was making negative comments about Mormons. I thought, now, wait a minute — isn't Newt in favor of multiple wives?"

Laughter rumbled from the audience followed by applause. The polygamy punch line is a familiar one when it comes to poking fun at Mormons — as though Mormons and polygamy are synonymous in mainstream media. Ironically, the practice that's most linked to Mormons is a practice most Mormons oppose, according to a groundbreaking new study of Mormons in America released Thursday by the Pew Research Center's Forum on Religion and Public Life.

According to the study, members of The Church of Jesus Christ of Latter-day Saints unequivocally reject polygamy — only 2 percent said the practice is morally acceptable — evidence of a yawning gap in what Mormons believe and how they are perceived. Mormons' opinions are overwhelmingly conservative, the study shows, but in many ways, their views are also surprising — especially when it comes to opinions on moral issues, divorce, homosexuality and polygamy.

Morality

Mormons also take a significant stance on moral issues in other areas, such as divorce, sex outside of marriage and consumption of alcohol.

Although teachings from the LDS Church emphasize the importance and eternal nature of the family, only 25 percent of Mormons surveyed said divorce is morally wrong, according to the study. That means Mormons are slightly less morally opposed to divorce than the general public.

"For Catholics, divorce does not exist. They think it is not only wrong but it is impossible," said Matthew Bowman, member of a board of expert advisers to the Pew Research Center for the study and author of "The Mormon People," a book on the history of the LDS Church. "That has not been true for Mormons. There is theological space for divorce within Mormonism. It is undesirable, but Mormons recognize it is sometimes necessary and sometimes the right thing to do."

Other moral views revealed in the survey — 54 percent said drinking alcohol was morally wrong, compared with 15 percent of the general public — set Mormons apart, Bowman says. The assumption on the part of non-Mormons is that if Mormons think drinking alcohol is wrong, then they must think everyone who imbibes is morally flawed. That apprehension can make people suspicious of Mormons, and wary of an elitist attitude, he says.

Differences in moral viewpoints can create a stumbling block for Mormon acceptance — not only in high-profile arenas, such as a presidential election, but also in communities.

"What you find throughout the report is a tension," said David Campbell, assistant professor at Notre Dame and an adviser on the study. "Mormons like to use the phrase, 'Be in the world but not of the world.' They are certainly living their lives in the world. They are active and involved in their communities, but they have these beliefs and practices that set them apart a little bit, and sometimes there is conflict."

Homosexuality

Mormons have some of the most conservative opinions when it comes to homosexuality. The survey asked Mormons if homosexuality should be accepted by society or discouraged by society, with an option for neither, both or "don't know." The response — 26 percent said homosexuality should be accepted, 65 percent said it should be discouraged — puts Mormons as the least likely to say homosexuality should be accepted by society. But a 26 percent acceptance rate, with roughly 1 in 4 Mormons saying homosexuality should be accepted, might be surprisingly high to some.

Of particular interest is the fact that only 8 percent of Mormons surveyed identified themselves as liberal, and 66 percent said they were conservative. That means some of those who said homosexuality should be accepted also identify themselves as politically conservative, Bowman says. That distinction illustrates the complexity of Mormons' opinion on sexuality — that it is rooted more in religious precepts than politics.

Still, it's difficult to draw a conclusion about Mormons' views on homosexuality based on the study, says Pew Research Center adviser Terryl Givens, professor of literature and religion at the University of Richmond.

"Results need to be viewed cautiously," Givens says. "Official LDS pronouncements insist there is a distinction between (sexual) orientation and behavior, but the survey blurs that difference, probably leaving many Mormons unsure how to answer that question. What is clear, however, is that Mormons are trending toward greater acceptance of same-sex relationships, just as society as a whole is, although by a much smaller percentage."

Polygamy

At one point 120 years ago, some Mormons practiced plural marriage, hence the association between Mormons and polygamy. The practice was discontinued in 1890, but the cultural association persists, perhaps in part because Mormons are sometimes confused with members of the Fundamentalist LDS Church, a polygamist group not affiliated with The Church of Jesus Christ of Latter-day Saints.

In the October-November 2011 study of a national sample of 1,019 Mormons, 86 percent said polygamy is morally wrong. That's a number that surprises Bowman.

Were it not for the confusion surrounding Mormons and the FLDS Church practice of plural marriage, Bowman says that statistic might not be as high.

"It's my experience that Mormons have a fraught relationship with polygamy," Bowman said of the study results. "There is a sense that rejecting polygamy identifies a member of the LDS Church and distinguishes us from the fundamentalists. That is a cultural signifier as much as a theological statement."

Some who responded to the survey, 11 percent, said polygamy is not a moral issue.

Email: achoate@desnews.com