MYRTLE BEACH, South Carolina (Reuters) - Republican presidential hopefuls attacked Mitt Romney's record in business and government on Monday and challenged him to release his tax returns, but the front-runner emerged largely unscathed from a South Carolina debate.
Newt Gingrich, Rick Perry and Rick Santorum questioned Romney's accomplishments and urged voters to take a critical look at the former Massachusetts governor as they tried to halt his growing momentum in the race to pick a challenger to President Barack Obama.
"We need to satisfy the country that whoever we nominate has a record that can stand up to Barack Obama in a very effective way," said Gingrich, the former House speaker, defending his questions about Romney's work at a private equity firm that critics say slashed jobs and plundered companies.
"There was a pattern in some companies, a handful of them, of leaving them with enormous debt and then within a year or two or three having them go broke. I think that is something he ought to answer," he said.
Romney's firm, Bain Capital, has become a flashpoint in the race in recent weeks, although the candidates have eased off their criticism on the campaign trail at the urging of some Republicans.
Romney defended his record at Bain, saying he invested in more than 100 businesses and had a mixed but overall successful record of job creation.
"If people want to have someone who understands how the economy works, having worked in the real economy, then I'm the guy who can best post up against Barack Obama," Romney said.
Just hours before the debate former Utah Governor Jon Huntsman dropped out of the Republican race and endorsed Romney, bolstering his drive for his party's nomination. Romney won the first two state nominating contests in Iowa and New Hampshire this month.
Romney leads polls in South Carolina, and a win here on Saturday would put him on an almost certain path to clinching the nomination to face Obama in November.
The candidates will get another crack at Romney at a debate in Charleston on Thursday, less than 48 hours before South Carolina Republicans start voting.
Perry, the Texas governor, challenged Romney during the nearly two-hour debate to release his tax returns. Perry and Gingrich have been raising the issue on the campaign trail in the last few days.
"I hope you'll put your tax records out there this week so the people of South Carolina can take a look and decide if, you know, we've got a flawed candidate or not," Perry told Romney.
Romney did not firmly commit to releasing his records but said historically candidates have released them around April. "That's probably what I'll do," he said.
Santorum, a former U.S. senator who is battling Gingrich and Perry for the support of conservatives unwilling to back the more moderate Romney, criticized Romney's Super PAC funding group for airing ads that he said made false claims about his record.
Romney said he had no control over the outside Super PAC, which has spent millions in Iowa, New Hampshire and South Carolina on tough ads criticizing Gingrich and Santorum.
"If they ever run an ad or say something that is not accurate, I hope they either take off the ad or make it correct," Romney said.
Gingrich drew a standing ovation from a crowd drawn heavily from a convention of conservative Tea Party activists in Myrtle Beach when he defended past comments about the poor that a moderator said could be viewed as insulting.
"I believe every American of every background has been endowed by their creator with the right to pursue happiness," he said. "If that makes liberals unhappy, I'm going to continue to find ways to help poor people learn how to get a job, learn how to get a better job and learn someday to own the job."
Libertarian U.S. Representative Ron Paul drew boos from the crowd during a discussion of Afghanistan and the Taliban when he said the United States should be careful about intervening in foreign lands.
"This country doesn't need another war," he said. "We need to quit the ones we're in."
Perry said the federal government had become too intrusive into state affairs, and cited efforts in South Carolina to block the institution of a new voter law that requires photo identification to vote.
"I'm saying the state of Texas is under assault by federal government. I'm saying also that South Carolina is at war with this federal government," he said.
Editing by Alistair Bell and Jackie Frank