"There are some who would have a presidential candidate describe and explain his church's distinctive doctrines," Romney said, noting that that type of religious test is prohibited in the U.S. Constitution. "No candidate should become the spokesman for his faith," he said.

Romney described the American values all faiths share, including seeing liberty as "a gift of God, not an indulgence of government." He said he was taught to "honor God and love thy neighbor," and recalled seeing his father, the late Michigan governor and onetime presidential candidate George Romney, march with civil rights leader Martin Luther King.

"My faith is grounded on these truths," he said. "You can witness them in Ann and my marriage and in our family. We are a long way from perfect, and we 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 referred to early LDS leader Brigham Young along with other American religious leaders who were persecuted for their beliefs before constitutional guarantees were firmly in place. He compared the faith-based culture of the United States with what he said was Europe's indifference to faith and the violence of radical Islamists.

Sonja Eddings Brown, a former KTVX Channel 4 reporter who now works as a media consultant in Los Angeles, said Romney did not need to go into more detail about his church. "As a Mormon, I feel like his example is really the strongest message," said Brown, who attended the speech.

Jay Sekulow, a lawyer with the American Center for Law and Justice founded by Pat Robertson, and a Romney adviser, said the speech was enough to change "the direction and tone of the debate" over whether a Mormon could be president.

Romney never mentioned by name the other presidential candidate who felt compelled to defend his religion in a high-profile speech — John F. Kennedy. Kennedy also came to Texas, where he confronted critics of his Catholic faith in 1960. But unlike Romney, Kennedy delivered his address before a group of seemingly skeptical Baptist ministers and even took their questions afterward.

When Romney's speech ended, he walked among the members of his handpicked audience and accepted their congratulations — and even a few hugs from longtime friends, like Utah developer Kem Gardner.

"I told him what I honestly felt, that it was extraordinary," Gardner said. "This was not a speech to Utah. This was a speech to the nation — not a speech to Mormons." He said he'd been against Romney offering what some have called a "Mormon moment" about the faith.

There was an echo of Kennedy's speech when Romney said church leaders would not influence him as president. "Their authority is theirs, within the province of church affairs, and it ends where the affairs of the nation begin."