The president of South Carolina’s largest religious organization said Mitt Romney’s Mormon faith will be a bigger concern to voters in the “morally conservative” early-voting state than Newt Gingrich’s infidelities.

Rev. Brad Atkins, the president of the South Carolina Baptist Convention, which includes nearly 2,000 churches and a million members, told South Carolina's Patch newspaper on Monday that both Romney and Gingrich could struggle in the Palmetto State because of these issues.

“In South Carolina, Romney's Mormonism will be more of a cause of concern than Gingrich's infidelity," Atkins said. “Conservatives can process and pray their way through the issue of forgiveness toward a Christian that has had infidelity in their life, but will struggle to understand how anyone could be a Mormon and call themselves ‘Christian.’ ”

South Carolina's primary contest, which will take place on Jan. 21, will be the third vote in the GOP presidential race and thus critical for the Gingrich campaign. The former House Speaker spiked in the polls earlier this month, but recent polls show that support has collapsed.

Gingrich has fallen from first to third in Iowa, and Romney is poised to win in New Hampshire by a wide margin. Gingrich leads in South Carolina by 18 points, according to the Real Clear Politics average.

“(Gingrich's past) will probably have a greater impact on his electability in South Carolina than some other states because, at least to some degree, we remain a morally conservative state,” Atkins continued. “However, we have to accept his confession that he has made mistakes, has asked for God's forgiveness in regards to those, and that he is deeply committed to his wife now. There will be many voters in not only South Carolina, but also around our nation that will pray over this issue as they consider him as a potential candidate for president.”

With the exception of a few isolated incidents, Romney’s faith hasn’t been much of an issue in the GOP primary so far.

Last week, a top Gingrich aide in Iowa was dismissed after calling Mormonism a “cult,” and in October, Pastor Robert Jeffers said the same thing while introducing primary opponant Rick Perry at the Value Voters Summit in Washington, D.C.

On the other hand, Gingrich’s past marital problems have been at the forefront since his rise in the polls.

“I’ve always been of the opinion that if you cheat on your wife you’ll cheat on your business partner, so I think that issue of fidelity is important,” Perry said at a GOP debate in December. “It’s a characteristic of which people look at other individuals, whether it’s in their business lives, or in their personal lives, or picking someone to serve in public office for them.”

“I think that sends a very powerful message," he continued, "if you will cheat on your wife, if you will cheat on your spouse, then why wouldn’t you cheat on your business partner, or why wouldn’t you cheat on anybody for that matter?”

Gingrich is on his third marriage and has admitted to past infidelities, but says those days are behind him and that he repented when he joined the Catholic church.

“In my case, I’ve said out front openly — I’ve made mistakes at times, I’ve had to go to God for forgiveness, I’ve had to seek reconciliation,” he said. “But I’m also a 68-year-old grandfather, and people have to measure now whether I’m a person that they can trust.”

Atkins said Christian voters will give Gingrich the benefit of the doubt, but that the door was open for a more values-oriented candidate like Perry or Michele Bachmann.

“Since most believers have had at least some moral failings, our only consideration should be where they are presently according to their own testimony. Christians must always give the benefit of the doubt. Where the candidate is now is the main issue," Atkins said.

"Both Perry and Bachmann will most likely fare better in South Carolina because of their openness to discuss their faith, but Gingrich can also speak about his Christian faith and values very openly as well.”