Presidential candidate Newt Gingrich said Saturday that Republicans will err if they don't scrutinize Mitt Romney's role in a private equity firm called Bain Capital.
Gingrich, the former House speaker, said President Barack Obama will hammer away at Bain if Romney is the nominee this fall.
"I don't see how you can expect us to have a presidential campaign in which an entire sector is avoided," Gingrich said on a Fox News program that included five of the six Republican candidates. Each fielded South Carolina voters' questions for almost 20 minutes.
Many Republican and conservative leaders have rebuked Gingrich for criticizing Romney's role at Bain. The private equity firm had a mixed record of job-creation at the companies it restructured in the 1980s and `90s.
Program host Mike Huckabee, who ran for president in 2008, gently reprimanded Gingrich for citing Romney by name. The candidates appeared separately, never confronting each other. Rep. Ron Paul of Texas did not participate.
The South Carolina GOP primary is Jan. 21.
Romney, the former Massachusetts governor, said he wants the federal government "out of the housing business" so the free market can work. Mortgage interest payments should remain tax-deductible, he said.
When a woman said expressions of Christian faith are under attack, Romney, a Mormon, said, "I will stand up for the ability of Americans to worship the god they choose." That would include public displays of manger scenes, menorahs and other religious symbols, he said.
Former Utah Gov. Jon Huntsman was asked why he supports legalized abortion in cases of rape and incest if he believes life begins at conception.
"I am pro-life," Huntsman said. "I have stipulations." Exceptions for rape and incest represent "where I am. I always have been, and I hope it's good enough for you," he said.
Former Sen. Rick Santorum noted that he does not support legalized abortions in cases of rape or incest. But he supports the death penalty, he said, because it does not involve "innocent life."
Santorum acknowledged voting to raise the federal debt ceiling at least five times while in Congress. But he said he consistently worked to reduce federal spending and to make the government more efficient.
Texas Gov. Rick Perry touted his call for a 20 percent flat tax, which would eliminate many existing loopholes. He would keep the deductibility of charitable gifts, local taxes and mortgage interest payments, he said.
Perry said he would dramatically reduce federal intervention in state actions regarding labor, the environment, voting laws and other matters.