Some conservative Christians have questioned the intensity of Romney's opposition to abortion, as he said he would not seek additional restrictions when he was running for governor. And some conservative evangelicals also wonder about Mormonism. On the Web site of the Christian Broadcasting Network, another Robertson entity, a page called "How Do I Recognize a Cult?" says that "when it comes to spiritual matters, the Mormons are far from the truth."

In private meetings with conservative leaders and members of Congress, Romney has argued that his experiences dealing with stem cell research as governor hardened his antiabortion views, and he tried to explain misconceptions about his faith.

But publicly, he has emphasized he is a "person of faith" and said the Mormon Church won't be instructing him about how to conduct his campaign or presidency. To be sure, Mormons are major Romney backers; data from his campaign finance records in his three months as a presidential candidate showed that Provo, Utah, has the Zip code where he raised most of his money. Provo is the home of Brigham Young University, his alma mater.

Romney aides have been repeatedly asked if the candidate will deliver an address explaining his religion, as John F. Kennedy did in 1960. They've generally dismissed the idea, but without foreclosing the possibly. They argue that voters are more concerned about Romney's views on issues than the particulars of his faith, although some published polls have shown that sizable numbers of Americans would be reluctant to back a Mormon president.