WASHINGTON (AP) -- Newt Gingrich is trying to preserve his rapid rise in the GOP presidential race by defending his most controversial stands without appearing to be the thin-skinned hothead his critics often describe.
The former House speaker seemed to accomplish that goal in Saturday's debate in Iowa. His challenge will be to sustain the strategy while rivals attack him on the airwaves and the ground, and to convince conservative voters that he's their champion despite his occasional departures from orthodoxy.
Polls suggest Gingrich is the likeliest alternative to former Massachusetts Gov. Mitt Romney heading into the leadoff Iowa caucuses on Jan. 3. So far, he has reacted with a steely calm.
He may ruffle feathers by telling unpleasant truths, Gingrich says, but he's not such an incendiary politician that he's unworthy of being commander in chief.
In the latest debate, Gingrich admitted wrongdoing and regret in only one area: the marital infidelities involved in his two divorces.
"I said upfront, openly, I've made mistakes at times," he said. "I've had to go to God for forgiveness." Voters have every right to examine such matters, he said, and "people have to render judgment."
Noting that he is "a 68-year-old grandfather," Gingrich added: "I am delighted at the way people have been willing to look at who I am, to look at what my record has been."
The answer seemed to defuse the potentially emotional issue. The debate quickly moved to other topics, on which Gingrich was less apologetic.
He defended his former support for requiring people to obtain health insurance, saying it once was a popular stand with conservatives.
"In 1993, in fighting HillaryCare, virtually every conservative saw the mandate as a less-dangerous future than what Hillary was trying to do," Gingrich said.
Hillary Rodham Clinton was leading the health care effort for her husband, President Bill Clinton.
"I frankly was floundering, trying to find a way to make sure that people who could afford it were paying their hospital bills, while still leaving an out so libertarians could not buy insurance," Gingrich said. "It's now clear that the mandate, I think, is clearly unconstitutional. "
Mandated health insurance is at the heart of the 2010 federal law passed at President Barack Obama's urging, and many conservatives despise it. It also is featured in the Massachusetts law pushed by Romney when he was governor.
The other GOP candidates painted both men as too liberal on the topic.
"Newt Romney" will be unable to challenge Obama credibly on health care, said Rep. Michele Bachmann of Minnesota.
Romney has stayed at or near the top of the GOP polls for months, while others rose and fell. He has more money and organization than Gingrich. But some conservatives still revere Gingrich for his role in the 1994 Republican takeover of the House majority, and for his decades of writing books and making speeches about his political philosophies.
Romney renewed his effort to portray Gingrich as too erratic and bombastic to be president. The topic was Gingrich's recent assertion that Palestinians are an "invented" people, a description that suggests Palestinians have no legitimate claim to their own state in the Middle East. That would run counter to long-term U.S. policy and to Israeli efforts to find a two-state solution to the region's turmoil.
It was "a mistake on the speaker's part," Romney said. "We're going to tell the truth, but we're not going to throw incendiary words into a place which is a boiling pot when our friends, the Israelis, would probably say, `What in the world are you doing?'"
"I'm not a bomb thrower, rhetorically or literally," Romney said.
Gingrich didn't back down. "I feel quite confident an amazing number of Israelis found it nice to have an American tell the truth," he said.
Gingrich cast himself as a risk-taking, unorthodox politician in that regard, but at other times he played by the rules. He made a pitch to supporters of Texas Gov. Rick Perry and former Pennsylvania Sen. Rick Santorum by praising the two on constitutional and Iran policies, respectively.
As before, Romney contrasted his many years as a businessman with Gingrich's two decades in Congress and lengthy career as a Washington-based consultant.
Gingrich shot back: "The only reason you didn't become a career politician is you lost to Teddy Kennedy in 1994" in a Senate race.
The debate offered one of the last chances for second-tier candidates to gain traction before voting starts in Iowa and, one week later, in the New Hampshire primary Jan. 10.
Perry avoided the gaffes that have hurt him before, and reasserted his claim to be a job-creating leader with no Washington ties. The nation needs lower taxes, less regulation and more common sense, he said, "and an outsider like Rick Perry is going to do that."
Rep. Ron Paul of Texas drew loud cheers from fans of his libertarian philosophies. Iowa Republicans say it's conceivable that Paul could win in Iowa next month.
But many party insiders say Paul's positions are too radical for mainstream America. Examples include his call for extraordinarily deep cuts in federal spending and services.
"If we took that oath of office seriously in Washington," Paul said in the debate, "we'd get rid of 80 percent of the government."
With former Utah Gov. Jon Huntsman skipping the debate and businessman Herman Cain gone from the race, the stage contained only six candidates. That gave Bachmann and Santorum, who have struggled in the polls, a bit more time before the cameras.
Given the campaign's ups and downs, and Romney's inability to pull away, perhaps Bachmann or Santorum will make a late surge. But Gingrich is drawing the main attention for now. His calm-but-unapologetic style will be tested over the next three weeks.