But Katon Dawson, the Republican chairman in South Carolina, said he thought Romney had made significant progress in dealing with those concerns. "I have heard him on his personal faith and on his character and conviction and the love for his country," Dawson said. "I have all confidence that he will be able to answer those questions, whether they be in negative ads against him or in forums or in debates."

Romney's candidacy has stirred a flurry of discussion about faith and the White House unlike any since Kennedy, including a remarkable debate that unfolded recently in The New Republic. Damon Linker, a critic of the influence of Christian conservatism on politics, described Mormonism as a "theologically unstable, and thus politically perilous, religion."

The article brought a stinging rebuttal in the same publication from Richard Lyman Bushman, a Mormon who is a history professor at Columbia University, and who said Linker's arguments had "no grounding in reality."

Romney is not the first Mormon to seek a presidential nomination, but by every indication he has the best chance yet of being in the general election next year. His father, George Romney, was a candidate in 1968, but his campaign collapsed before he ever had to deal seriously with questions about religion.

Hatch said his own candidacy in 2000, which was something of a long-shot, was to "knock down prejudice against my faith."

"There's a lot of prejudice out there," Hatch said. "We've come a long way, but there are still many people around the country who consider the Mormon faith a cult."

But if Romney has made progress with evangelicals, he appears to face a larger challenge in dispelling apprehensions among the public at large about the church. A national poll by The Los Angeles Times and Bloomberg last June found 37 percent said they would not vote for a Mormon for president.

Romney offered assurances that seemed to reflect what Kennedy told the nation in discussing his Catholicism some 50 years ago. He said the requirements of his faith would never overcome his political obligations. He pointed out that in Massachusetts, he had signed laws allowing stores to sell alcohol on Sundays, even though he is prohibited by his faith from drinking, and to expand the state lottery, though Mormons are forbidden from gambling. He also noted that Mormons are not exclusively Republicans, pointing to Sen. Harry Reid of Nevada, the Democratic majority leader.

"There's no church-directed view," he said. "How can you have Harry Reid on one side and Orrin Hatch on the other without recognizing that the church doesn't direct political views. I very clearly subscribe to Abraham Lincoln's view of America's political religion. And that is when you take the oath of office, your responsibility is to the nation, and that is first and foremost."

He said he was not concerned about the resistance in the polls. "If you did a poll and said, 'Could a divorced actor be elected as president, would you vote for a divorced actor as president,' my guess is 70 percent would say no. But then they saw Ronald Reagan, they heard him, they heard his vision they heard his experience, they said I like Ronald Reagan, I'm voting for him."