Updated

Just days after Sen. Orrin Hatch, R-Utah, himself a Mormon, predicted that Mitt Romney's opponents would seek to use his faith against him, Democratic Montana Gov. Brian Schweitzer made controversial remarks linking Romney's family to polygamy.

Schweitzer theorized that Romney would probably like to have a conversation about immigration with Hispanics, but that it would be difficult for Romney because his father was "born on a polygamy commune in Mexico."

The former governor told Fox News, "My dad's dad was not a polygamist," adding, "My dad grew up in a family with a mom and a dad and a few brothers and one sister."

Schweitzer's office insists the remarks had "nothing to do with Romney's faith or his Church," but the comments have once again put Romney's Mormonism in the spotlight.

Earlier in the primary season, both New York Times columnist Charles Blow and MSNBC political contributor Joan Walsh apologized after tweeting "inappropriate" remarks toward Romney regarding the Mormon faith and some of its most sacred practices.

Following Schweitzer's remarks, a spokesperson for the Obama campaign quickly denounced any attempt to attack a candidate's religion, calling the move "out of bounds."

According to Larry Sabato, director of the University of Virginia's Center for Politics, the reaction from the Obama campaign was a smart move. "I noted even the Obama campaign recognized immediately the dangers of what Gov. Schweitzer said, and in essence, reprimanded him, and came out very strongly suggesting that that was inappropriate."

Democratic strategist Ryan Clayton says all sides are best advised not to try to use religion in the political arena.  "Faith and politics, when you mix them together, it becomes kind of a tinderbox and it can explode in your face."

A recent ABC News/Washington Post poll revealed that 80 percent of those surveyed said Romney's Mormonism is not a major factor in their decision to either support or oppose him.

At least 15 members of Congress identify themselves as Mormons, including Senate Majority Leader Harry Reid, D-Nev.  Fox News reached out to Reid's office to ask whether he has taken the same kind of heat as Romney over their shared faith.  Though he did not respond to our request for an interview, in the past Reid has said, "I don't think my faith is a hindrance to what I do."