Two Republican presidential candidates refused to say Sunday whether they believe Mitt Romney, a Mormon, is a Christian, while a third said he doesn't agree with a Texas pastor who called the religion a "cult."

Businessman Herman Cain and Minnesota congresswoman Michele Bachmann declined to answer questions about Romney's Mormon religion.

"He's a Mormon, that much I know," Cain said. "I am not going to do an analysis of Mormonism versus Christianity for the sake of answering that."

Bachmann called the issue a distraction.

"I think what the real focus is here, is on religious tolerance. That's really what this is about," Bachmann said. "To make this a big issue is ridiculous right now, because every day I'm on the street talking to people. This is not what people are talking about."

Former Pennsylvania Sen. Rick Santorum, who runs in the GOP presidential campaign as a social conservative, was more direct, saying _ as Texas Gov. Rick Perry did Friday _ that he didn't consider Mormonism a cult.

"I'm not an expert on Mormonism. All I know is that every Mormon I know is a good and decent person, has great moral values," Santorum said.

But when asked if he believed Romney is "a true Christian," Santorum spoke somewhat haltingly: "Mitt Romney is a true, he says he's a Christian. I believe he said Christian."

In Romney's 2008 campaign, Mormons said they felt maligned by claims they aren't Christian. The scriptures used by the Church of Jesus Christ of Latter-day Saints include the Old and New Testaments, and sacred books that contain the revelations of their 19th century founder Joseph Smith.

The recent questions about Romney's religion surfaced Friday after a Baptist pastor told reporters after introducing Perry at a forum that Romney was "not a Christian." Robert Jeffress, who made similar comments in 2008, also told reporters that Mormonism is a "cult."

Former House Speaker Newt Gingrich, another GOP presidential contender, criticized Jeffress' comments on Sunday, calling them "very unwise and very inappropriate."

"I think that none of us should sit in judgment on somebody else's religion," Gingrich said. "I think he's a Mormon and Mormons define themselves as a branch of Christianity."

Cain and Bachmann appeared on CNN's "State of the Union." Santorum appeared on "Fox News Sunday." Gingrich appeared on CBS's "Face the Nation."