"Of those who correctly know that Mormons do not practice polygamy, 39 percent would definitely consider voting for one, compared to only 26 percent among the rest of the voters," Lawrence said. "Similarly, 83 percent of voters who know that Mormons do not practice polygamy would vote for a well-qualified nominee of their party who happens to be a Mormon, whereas only 68 percent of those who believe Mormons practice polygamy, or are not sure, would vote for a Mormon nominee."
Nearly half (46 percent) wrongly think that Mormons either "definitely" or "probably" practice polygamy.
Some of the confusion may stem from polygamous groups including the Fundamentalist Church of Jesus Christ of Latter-Day Saints, led by convicted child abuser Warren Jeffs that broke away from the main LDS Church yet continue to believe in many of its tenets and still describe themselves as "Mormon."
Brigham Young University political scientist Quin Monson suspects that many respondents lumped a lot of groups together under the label of "Mormon" when they answered the polygamy question. But many are thinking about Romney and/or Huntsman when they answer the voter question, he said, and may be thinking those candidates are part of the Mormon group that doesn't practice polygamy.
When the survey asked voters about the Mormon nickname, 30 percent said it applies only to the LDS Church, 25 percent had no opinion, while 45 percent "feel it applies to all groups that believe the Book of Mormon," said Lawrence, whose book, Mormons Believe…What?! Fact and Fiction About a Rising Religion, will be released later this month.
"We have an identification problem we are trying to explain to the world," Lawrence said. "Today's polygamists are not Mormons, and Mormons are not polygamists. Our members bristle when people mistake the two."
LDS Church headquarters gets fewer questions about polygamy than it did a decade ago, spokesman Scott Trotter said Monday.
The faith's official position is that the church discontinued its practice of polygamy in 1890 and those who practice polygamy are not members of the church.
"When reporters refer to polygamists as Mormons, we correct them," Trotter said. "They owe it to their readers to be clear. When people hear 'Mormon,' they think of the Mormon Tabernacle Choir, Mormon missionaries in white shirts and ties and Mormon temples. Stories that don't point out the difference are confusing, inaccurate and do a disservice to the news-consuming public."
But Anne Wilde, co-founder of Principle Voices, an educational-advocacy group for plural marriage, defends her use of "Mormon fundamentalist."
"A Mormon is someone who believes in the Book of Mormon and Joseph Smith and basic [Mormon] teachings and we do," Wilde said. "We always make the distinction between us and the main body of Mormons clear."
The national poll, conducted July 6-13, has a margin of error of 3.1 percentage points.
"We are trying everything we can think of to get the truth out," Lawrence said. "But we clearly have a long way to go."