COLUMBIA -- In a state grappling with high unemployment, Mitt Romney's GOP opponents figured they had an issue that could derail his hopes for a third straight win here in South Carolina.

But was their talk of Bain in vain?

Both former Speaker Newt Gingrich and Texas Gov. Rick Perry were far more quiet Thursday about Romney's history with Bain Capital -- a venture capital company that he ran before getting elected governor of Massachusetts. The company shut down some companies that it had bought and laid off workers, prompting Perry to dub Romney a "vulture capitalist" earlier in the week.

But this line of attack has drawn a steady stream of ire from many across the GOP spectrum.

During a Romney rally Wednesday, Gov. Nikki Haley said she is "proud of all of our Republican candidates ... but we have a real problem when we have Republicans talking like dang Democrats against the free market. We believe in the free market."

Former Arkansas Gov. Mike Huckabee, who is hosting a FOX News forum with the candidates Saturday in Charleston, said he was surprised to see so many Republicans "embrace that left-wing argument against capitalism."

"It's terrible for the workers who lose their jobs, and nobody likes to see viable companies looted and destroyed," Huckabee added. "But if downsizing can turn around a failing company, then at least it prevents all the jobs from being lost."

State Rep. Chip Limehouse, R-Charleston, said he still supports Perry but is glad he seems to be backing away from calling Romney a "vulture capitalist."

"To go back and second guess Governor Romney and the decisions he made as a private businessman, I think that's off target in a political contest. It sounds like Democrats to me," Limehouse said.

While campaigning on Daniel Island, former Pennsylvania Sen. Rick Santorum noted he abstained from criticizing Romney over Bain. "I believe in capitalism," Santorum said, but he added that Romney's background makes it harder for him to relate to voters.

Larry Sabato, director of the University of Virginia's Center for Politics, said the Bain issue might sway some of South Carolina's white working-class voters away from Romney.

"But it is also possible that South Carolina's pro-business attitude, especially among Republicans, will provide Romney some cover," Sabato added.

During two Columbia campaign stops Thursday, Gingrich did not mention Bain and implied the criticism he faced was because he wanted an audit of the Federal Reserve and the billions given to bail out big banks.

"I've been asking some questions, and I am amazed at the intensity of the challenges," he told a senior fair at the Columbia Fair Grounds.

"It's somehow thought if you ask questions, you're somehow challenging the whole system," Gingrich added. "The American people have the right to know what has been happening to their economy."

As Perry walked through Summerville Thursday, he briefly addressed the shots he took at Romney. "We just brought up the issues that needed to be brought to the table," he said.

Perry's comments did cost him one key supporter, former state GOP chairman Barry Wynn, who also endorsed Romney on Thursday. Wynn said Perry was trying to have it both ways by attacking capitalism and boasting about his job growth credentials.

Romney's campaign announced the backing of two dozen South Carolina business leaders, including several from Charleston: Richard E. Coen, E. Bart Daniel, Henry Fishburne Jr., Joseph Griffith Jr., Matthew Hubbell, John von Lehe and Anita G. Zucker.

Amanda Henneberg, a Romney campaign spokeswoman, said it is sad to see how desperate Romney's opponents have become. "As they flail about with anti-free enterprise rhetoric, Gov. Romney will continue to talk about his vision for the country and the need to get Americans back to work," she said.

Even if Republicans remain relatively silent on Bain, the issue will be kept alive by others.

South Carolina Democratic Chair Dick Harpootlian mentioned it Thursday as Romney visited the Upstate, where Bain shut down a plant years ago. "In his best Gordon Gecko smirk, he explains this is the free market at work," Harpootlian said.

Asked if the Democrats will continue to mention Bain if Romney becomes the GOP nominee, Sabato put the odds at between 99.9 percent and 100 percent.

"They consider it a big winner," he added. "The fact that both Newt and Perry are now on videotape decrying Bain's practices is a godsend for Obama."