HBO is airing a television series, "Big Love," that features a man in Utah — where the LDS church is based — with three wives. Self-proclaimed "Mormon fundamentalist" Warren Jeffs, formerly on the FBI's Ten Most Wanted list, is facing multiple felony charges for sex crimes related to underage marriages among members of his breakaway church's 10,000 members in Utah and Arizona, who openly practice polygamy.

Romney has joked about polygamy, saying in various settings that to him, "marriage is between a man and a woman ... and a woman and a woman." But in serious moments he has called the practice "bizarre" and noted his church excommunicates those who engage in it.

An introductory film played at his fund-raisers and campaign appearances features his wife, Ann, talking about their 37-year marriage. Romney himself notes they started as high school sweethearts.

This month, Ann Romney tried a different tack, taking a lighthearted jab at her husband's main Republican competitors, Sen. John McCain, R-Ariz., and former New York City Mayor Rudy Giuliani, as she introduced Romney at a Missouri GOP dinner.

The biggest difference between her husband and the other candidates, Ann Romney said, is that "he's had only one wife."

McCain has been married twice; Giuliani three times.

The Romney campaign had no comment for this story.

Joseph Smith, who founded The Church of Jesus Christ of Latter-day Saints in 1830, quietly introduced polygamy. He believed it had roots in the Old Testament and was necessary to reach the highest salvation in heaven. Smith is believed to have had 33 wives.

Brigham Young expanded the practice after the church's migration from the Midwest to Utah, which began in 1846. He is said to have had 55 wives. Historical texts show Young also asked Orson Pratt to publicly proclaim the church's belief in polygamy in 1852.

In 1862, while Utah was a territory, President Abraham Lincoln signed the Morrill Anti-Bigamy Act, banning plural marriage. In 1882, Congress also passed the Edmunds Act, an anti-polygamy law. That was followed in 1887 by the Edmunds-Tucker Act, which disincorporated the church and threatened to seize its nonreligious real estate as part of the crackdown on polygamy.

In 1890, church President Wilford Woodruff issued "The Manifesto," in which he declared the church no longer taught or permitted plural marriages.

Nonetheless, the law of polygamy — Smith's revelation that God authorized polygamy — remains in Article 132 of the church's Doctrine and Covenants. In addition, Mormon widowers who remarry today believe they will live in eternity with their multiple wives.

Church genealogical records, among the most detailed and complete of any religion, show that two of Mitt Romney's great-great-grandfathers, Miles Romney and Parley P. Pratt, had 12 wives each.