"I will take care to separate the affairs of government from any religion, but I will not separate us from the God who gave us liberty," he said.

"There are some," he said, who "would prefer it if I would simply distance myself from my religion, say that it is more a tradition than my personal conviction, or disavow one or another of its precepts. That I will not do."

The Rev. Barry Lynn of Americans United for Separation of Church and State objected to Romney's description of the role of religious faith in government.

"I was particularly outraged that Romney thinks that the Constitution is somehow based on faith and that judges should rule accordingly," he said. "That's a gross misunderstanding of the framework of our constitutional system."

Romney has staked out conservative positions on abortion and gay marriage, but polls indicate that a quarter of evangelicals would be reluctant to vote for a Mormon.

Romney called that a religious test, which the founders prohibited in the Constitution.

"No candidate should become the spokesman for his faith. For if he becomes president, he will need the prayers of the people of all faiths," he said.

Romney's speech lasted about 20 minutes and was interrupted a dozen times by applause from the invited audience of several hundred people. He said the word "Mormon" only once, otherwise referring to "my religion," "my faith" and "my church."

He said he believes Jesus "is the son of God and savior of mankind," but acknowledged Mormon doctrine has different beliefs about the earthly presence of Jesus Christ. Some evangelicals are troubled that Mormons believe Jesus visited America and that the Bible is insufficient as a religious text.

Romney said those differences should not be "bases for criticism, but rather a test of our tolerance."

Unlike Thursday's speech in which Romney faced a friendly crowd, Kennedy spoke in 1960 to a group openly in opposition to having a Catholic as president.

The Alabama and Texas Baptist conventions, the National Association of Evangelicals and the president of the Southern Baptist Convention all came out in opposition. On Sept. 7, 1960, a group of 150 conservative Protestant leaders issued a statement warning that Kennedy would be "would be under extreme pressure from the hierarchy of his church to accede to its policies."

Kennedy delivered his speech five days later.