WASHINGTON (Reuters) - Republican presidential candidate Mike Huckabee said he considers his rival Mitt Romney’s Mormon faith a religion, not a cult, but questioned whether Mormons believe “Jesus and the devil are brothers.”

Republican presidential candidate, former Arkansas Governor Mike Huckabee, speaks during the Republican Party of Florida and Univision Spanish channel debate at the University of Miami in Miami, Florida December 9, 2007. REUTERS/Carlos Barria

Huckabee raised the question on his own in an interview to appear in The New York Times magazine on Sunday, and ignited a new flap in the up-for-grabs race to be the Republican Party’s nominee in the November 2008 presidential election.

Huckabee was asked if he considered Mormonism a cult or a religion. “I think it’s a religion,” he said in the interview, published on the newspaper’s Web site on Wednesday. “I really don’t know much about it.”

Then he asked: “Don’t Mormons believe that Jesus and the devil are brothers?”

Romney, who has tried to dispel conservative Christians’ worries about the Mormon faith, responded on NBC’s “Today” show on Wednesday.

“I think attacking someone’s religion is really going too far. It’s just not the American way. and I think people will reject that,” the former Massachusetts governor said.

“That’s been something that’s been leveled at our church over many many years and of course that’s been set straight now,” he added.

Huckabee, a Baptist minister and former Arkansas governor, has surged in public opinion polls and is now ahead of Romney in polls in Iowa, which holds its caucus, the first test of the U.S. state-by-state nominating season, on Jan 3.

He made the comment before Romney gave a major speech last week trying to dispel fears about his church, known formally as The Church of Jesus Christ of Latter-day Saints, particularly among conservative Christians, an important voting bloc. Romney said he believes Jesus Christ is the son of God and savior of mankind, and that his White House would not be controlled by his church.

Romney responded with a sharp attack on Huckabee’s positions on issues such as immigration and taxing and spending. “I think Mike was desperately hoping we would get through this without people taking a close look at his positions and his record,” he said.