In The New York Times, religion professor Randall Balmer discusses the faith and family values of leading Republican candidates for the 2012 Presidential Election.  An excerpt:

"Randall Balmer, who teaches American religion at Barnard College, offers two explanations for the support gap. First, Dr. Balmer says, one should not underestimate the evangelicals’ suspicion of Mormonism. “They do see it as a cult, and the Mormons have not been able to overcome that,” he says.

Dr. Balmer pointed to comments made in October by the Texas pastor Robert Jeffress, who called Mormonism a “cult” and said Mr. Romney is not a Christian. “What Jeffress said was utterly distasteful, but for evangelicals it is absolutely accurate,” Dr. Balmer said."

Dr. Balmer is the author of God in the White House: How Faith Shaped the Presidency from John F. Kennedy to George W. Bush.