He was an attractive candidate, with money, intelligence and institutional support. But no candidate of his faith had ever been elected president, and wherever he went this issue confronted him.
It got to the point that less than two months before the election, then-Sen. John F. Kennedy, D-Mass., had to go before a room of 300 or so Protestant ministers and declare, "I am not the Catholic candidate for president. I am the Democratic Party's candidate for president who happens also to be a Catholic."
Kennedy, the first Catholic president, went through a similar experience to what his fellow Bay Stater, former Gov. Mitt Romney, a Republican and a Mormon, is experiencing today.
Kennedy's Sept. 12, 1960 address to the Greater Houston Ministerial Association has become such lore that Richard Land of the Southern Baptist Convention told ABC News that when he met with Romney last year, "I told him that as far I was concerned, he needed to give a speech, he needed to 'do a JFK.'"
As Romney loses ground to former Baptist minister and Arkansas Gov. Mike Huckabee in Iowa, a state where 40 percent of the Republican voters identify themselves as born-again Christians, Romney seems indeed ready to "do a JFK."
He's even going to do it in Texas; Romney's campaign announced Sunday that on Thursday, the candidate will address the issue in a speech entitled "Faith in America" at the George H.W. Bush Presidential Library in College Station, Texas.
But if Kennedy's experience is any guide, one speech will not put the issue to rest. Historical amnesia aside, Kennedy's speech in Houston was not his first big public attempt to address and end discussion of the issue of his faith — far from it. Nor was it the end of the matter.
Kennedy, who as a senator had opposed federal aid to parochial schools and the appointment of a U.S. ambassador to the Vatican, had tried to put the issue to rest as early as March 1959, when Look magazine published an interview with him strongly asserting his belief in the separation of church and state.
"Whatever one's religion in his private life may be," Kennedy said, "for the officeholder nothing takes precedence over his oath to uphold the Constitution and all its parts."
That interview was so assertive Kennedy was criticized by Catholic media as overcompensating.
"He appears to have gone overboard in an effort to placate the bigots," wrote Baltimore's Catholic Review.
And yet the September 1960 speech is looked upon as the tipping point, when Kennedy may have put the issue to rest.
Land recalls that his minister attended the Greater Houston Ministerial Association speech and came back to his skeptical Baptist congregation to vouch for the Democratic nominee.
"I was 14 years old, and I lived in Houston, Texas," Land said, "and my pastor came back to our Baptist church and from the pulpit, he said: 'I have good news! President Kennedy told us that on public-policy issues, his church doesn't speak for him and he doesn't speak for his church. And that he's going to separate his Catholicism from his service if he's elected.' And people applauded all across the auditorium. They just thought it was a great thing."
Land says Kennedy "defended the right of a Catholic to run for president, and I think that's the kind of speech Romney needs to give."