CHICAGO — A presidential campaign focused on war, immigration and health care took a theological turn last week, raising questions more often debated in seminaries.

"Don't Mormons believe that Jesus and the devil are brothers?" asked Republican candidate Mike Huckabee, an ordained Baptist minister, in an interview to be published today in The New York Times.

Huckabee quickly apologized, but he already had thrown the spotlight back on Republican Mitt Romney, a Mormon, who said Thursday, "I think attacking someone's religion is really going too far."

Typically Americans like their leaders to be people of faith, without concerning themselves much about the details.

But as they encounter a faith that is little understood, comparatively new and growing fast, voters have expressed a sustained curiosity about what Mormons really do believe.

So what about the devil? According to members of The Church of Jesus Christ of Latter-day Saints, Huckabee's barb is a sound-bite reduction of a complex story.

Jesus and Satan do indeed have the same Heavenly Father, the church says. But during something of a family squabble, a spiritual war that took place before humanity came into existence, Satan rebelled — and Jesus was chosen to be the savior, given life on Earth.

"Lucifer will never experience mortality. He surrendered that when he chose to be disobedient and was cast out," said Elder M. Russell Ballard, a member of the church's Council of the Twelve Apostles.

Still, Mormons believe the devil is very much with us — especially in the first stage of our eternal journey. Mormons believe that humans are God's "spiritual children," creatures whose time on Earth is prefaced and followed by a different stages in heavenly career described in great detail in Mormon scriptures.

Instead of the conventional Christian picture of heaven and hell, Mormons believe there will be three degrees of glory after the resurrection. Humans will inherit their place in one, depending on their level of devotion.

Christopher Kimball Bigelow, a Mormon and co-author of "Mormonism for Dummies," notes that those who reach the highest level will share in God's creative powers — perhaps even creating other planets and life.

"God gives his children who pass the test with an A-plus all the power he has," Bigelow said. "He makes you a full partner in the family business."

That might sound strange to non-Mormon ears, but Kathleen Flake, a Mormon and associate professor of American religious history at Vanderbilt University said some of the concepts of a spiritual life outside our earthly experience date back to early Christianity.