(CBS/AP) Republican Mitt Romney, confronting voters' skepticism about his Mormon faith, declared Thursday that as president he would "serve no one religion, no one group, no one cause," and said calls for him to explain and justify his religious beliefs go against the profound wishes of the nation's founders.
At the same time, he decried those who would remove from public life "any acknowledgment of God," and he said that "during the holiday season, nativity scenes and menorahs should be welcome in our public places."
In a speech less than a month before the first nomination contests, Romney said he shares "moral convictions" with Americans of all faiths, though surveys suggest up to half of likely voters have qualms about electing the first Mormon president. (Read the text of the speech)
"I believe in my Mormon faith and I endeavor to live by it," Romney said. "My faith is the faith of my fathers. I will be true to them and to my beliefs."
Nonetheless, he strove to clarify his personal line between church and state, recalling a similar speech delivered by John F. Kennedy in 1960 as Kennedy sought to become the first Catholic elected president.
"It's important to remember that Romney's aims today are different than those of John F. Kennedy when he delivered his landmark speech on the same topic in 1960," said CBSNews.com senior political analyst Vaughn Ververs. "Kennedy was seeking to reassure voters during a general election that he would separate his Catholic faith from the presidency. Romney needs to reassure evangelical Christians that he shares their values."
"Let me assure you that no authorities of my church, or of any other church for that matter, will ever exert influence on presidential decisions," Romney said at the George Bush Presidential Library and Museum, 90 miles from Kennedy's speaking site in Houston. "Their authority is theirs, within the province of church affairs, and it ends where the affairs of the nation begin."
He added: "If I am fortunate to become your president, I will serve no one religion, no one group, no one cause and no one interest. A president must serve only the common cause of the people of the United States."
Romney's speech lasted about 20 minutes and was interrupted a dozen times by applause from the invited audience. He said the word "Mormon" only once, otherwise referring to "my religion," "my faith" and "my church."
He hoped the speech would allay concerns of Christian conservatives, some of whom have propelled former Arkansas Gov. Mike Huckabee to join him atop the polls in Iowa. Its caucuses kick off presidential voting next month.
Romney stated he is often asked on the trail whether he believes in Jesus Christ.
"I believe that Jesus Christ is the son of God and the savior of mankind," he said. While conceding Mormons have different beliefs about the earthly presence of Jesus Christ, "each religion has its own unique doctrines and history. ... Religious tolerance would be a shallow principle indeed if it were reserved only for faiths with which we agree."
Illustrating Romney's challenge, one of his own invited guests said he believes Mormons are not Christians.
"I don't think his Mormonism is a deal breaker for most Americans, but only Mitt Romney can close the deal," Richard Land, president of the Southern Baptist Convention's Ethics & Religious Liberty Commission, told ABC's "Good Morning America." Asked directly if he thought Mormons were Christians, Land said, "No, I do not."
Huckabee, who was a Southern Baptist preacher before entering politics, said that Romney's religion has no bearing on whether he would make a good president.
"It has nothing to do with what faith a person has - it's whether or not that person's life is consistent with how he lives it," Huckabee said Thursday on NBC's "Today." "If I had actions that were completely opposite of my Christian faith, then I would think people would have reason to doubt if this part of my life, which is supposed to be so important, doesn't influence me."
Romney, the former Massachusetts governor, also used the occasion to sound a call for greater religious thought in daily civic life, providing a near-history lesson as he recalled religion in American political life since the country's founding.
"The founders proscribed the establishment of a state religion, but they did not countenance the elimination of religion from the public square," he said.
CBS News' Scott Conroy reports that Romney has been reading Jon Meacham's book on the Founding Fathers and the role their faiths played in establishing the United States, and it was clear from his many references to the early days of the nation that their ideals of religious tolerance were heavy on the candidate's mind. (Read more from Conroy at the scene)
"The conviction of the inherent and inalienable worth of every life is still the most revolutionary political proposition ever advanced," Romney said.
In an appeal to social conservatives, he also invited James Bopp Jr., an anti-abortion activist who is Romney's special adviser on life issues.
Political foes have accused Romney of switching his positions on some social issues, like abortion, when it became expedient.
Romney addressed those concerns in the context of standing by his faith, saying, "Americans do not respect believers of convenience. Americans tire of those who would jettison their beliefs, even to gain the world."
Former President Bush introduced Romney, heightening public attention to the speech. Romney's backdrop on stage was 10 American flags and a replica of the presidential seal.
Serving as host at his presidential library, the elder Bush introduced Romney, pointed out members of the candidate's family in the audience and described Romney's father, former Michigan Gov. George Romney, as the father of volunteerism.
"He's certainly one of my mentors when it comes to points of light," said Mr. Bush, who enacted a volunteer initiative while president, called "Thousand Points of Light." Mr. Bush said he had no intention of endorsing a candidate. "I simply have too much respect for all of the candidates," he said. He called Romney a "good man" and said he considered him and his wife "good friends."
Beyond speaking about faith, Romney sought to use the publicity his speech generated to relaunch his campaign as the broader electorate begins to tune into his nomination fight against a field that includes former New York Mayor Rudy Giuliani and Arizona Sen. story=3193619>John McCain.
Striking a family chord, Romney's wife of 38 years, Ann, and four of the couple's five sons sat in the front row for the speech - two with their own children.
"We are a long way from perfect and we have surely stumbled along the way, but our aspirations, our values, are the self-same as those from the other faiths that stand upon this common foundation," Romney said. "And these convictions will indeed inform my presidency."
While Romney has been subject to some leafletting and phone calling pointing to religious differences between his faith and others, he has faced little religious bigotry or questions on the campaign trail. Instead, political realities played a role in his decision to make the speech.
In an AP-Yahoo poll last month, half said they had some problems supporting a Mormon presidential candidate, including one-fifth who said it would make them very uncomfortable.
Fifty-six percent of white evangelical Christians - a major portion of likely participants in the early GOP presidential contests in Iowa and South Carolina - expressed reservations about a Mormon candidate. Among non-evangelicals, 48 percent said it troubled them. Almost a quarter - 23 percent - of evangelicals said they were very uncomfortable with the idea.
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