Much as John F. Kennedy once confronted skeptics of his Catholic faith, Republican presidential candidate Mitt Romney said Sunday he will deliver a speech on religion as he seeks to become the first Mormon in the White House.

"Gov. Romney understands that faith is an important issue to many Americans," said campaign spokesman Kevin Madden. "He personally feels this moment is the right moment for him to share his views with the nation."

The speech, titled "Faith in America," will be given Thursday at Texas A&M University — about 100 miles from where Kennedy gave a celebrated speech on religion before he became the first Catholic president.

The announcement came a day after a poll by The Des Moines Register showed Romney falling behind Arkansas Gov. Mike Huckabee in the Jan. 3 Iowa caucuses that begin the Republican nominating process. An ordained Baptist minister, Huckabee is drawing strong support from conservative Christians.

"People don't understand what a Mormon is," said David Redlawsk, director of the University of Iowa Hawkeye Poll. "That leads to this new announcement about the religion speech."

A USA TODAY/Gallup Poll in February found that 72 percent would vote for a qualified candidate who is Mormon — compared with 94 percent for a black nominee and 88 percent for a woman.

Madden said Romney made the decision last week. The speech gives him a chance to "share his views on religious liberty, the grand tradition religious tolerance has played in the progress of our nation and how the governor's own faith would inform his presidency if he were elected," Madden said.

Kennedy spoke to the Greater Houston Ministerial Association on Sept. 12, 1960, two months before defeating Richard Nixon. In that speech, Kennedy said: "I am not the Catholic candidate for president. I am the Democratic Party's candidate for president who happens also to be a Catholic."

JFK biographer Robert Dallek said the situations are comparable in that Romney's religion presents a potential obstacle to getting elected. "Who knows whether it's a big a problem or small problem," Dallek said. "But they obviously think it's some kind of problem, so they're going to address it."

John Green, a fellow at the Pew Forum on Religion & Public Life and co-author of "The Diminishing Divide: Religion's Changing Role in American Politics," said Romney will be able to "address the skepticism of the Republican voters, particularly evangelical voters." But he added the risk is that "it could remind people of why they were skeptical."

Romney has said he'd welcome the chance to give such a speech. He told a New Hampshire gathering last month he is happy to talk about his faith.

"Is there going to be a special speech?" he said. "I sort of like the idea myself. The political advisers tell me no, no, no — it's not a good idea. It draws too much attention to that issue alone."