Following his solid debate performance, can Newt Gingrich be stopped?

In the crucial Iowa debate, Newt Gingrich came across as steady and principled, flexible or unwavering as he saw the need. The one major gaffe was Mitt Romney's $10,000 challenge to Rick Perry.

All eyes were on Newt Gingrich Saturday night in Iowa. And for debate-watchers – and especially Republicans still looking for a candidate they can get enthusiastic about – he did not disappoint.

The former House Speaker – a Washington insider publicly accused by many fellow Republicans and conservative commentators of being an unsteady rhetorical bomb-thrower with an out-sized ego – came across as steady and principled, flexible or unwavering as he saw the need.

And while some 70 percent of Iowa caucus-goers still say they could change their mind about whom they’ll vote for in next month’s first-in-the-nation nominating contest, Gingrich – leading in the polls – is the man to beat.

"He entered the debate with momentum and did not lose any momentum," Iowa Republican strategist Richard Schwarm told the Des Moines Register. "Despite being the main target, he was not damaged."

For every shot his rivals took, Gingrich seemed to have a ready and reasonable answer.

His one-time support for requiring most Americans to have health insurance?

That was in line with what many conservatives believed at the time as they tried to head off the national health care plans of then-first lady Hillary Clinton.

The notion of colonizing the moon and mining it for minerals?

“I’m proud of trying to find things that give young people a reason to study science, math and technology,” he said. “I grew up in the generation where the space program was real, where it was important and where frankly it is tragic that NASA has been so bureaucratized.”

His widely-reported and acknowledged marital infidelities?

Noting that he is "a 68-year-old grandfather" (whose granddaughter was in the audience urging him to smile more), he addressed the question head-on, noting that “people have to render judgment.”

"I said upfront, openly, I've made mistakes at times," he said. "I've had to go to God for forgiveness."

On Friday, Gingrich had told the Jewish Channel cable network that Palestinians are an “invented” people with no apparent right to their own country – an assertion contrary to the policies of Republican and Democratic administrations alike.

He later seemed to back-pedal, his campaign spokesman stating, “Gingrich supports a negotiated peace agreement between Israel and the Palestinians, which will necessarily include agreement between Israel and the Palestinians over the borders of a Palestinian state.”

Mitt Romney tried to paint the episode as an indicator that Gingrich is a “bomb-thrower” harming the Middle East peace process.

Likening his comments to former president Ronald Reagan’s reference to the Soviet Union as the “Evil Empire,” Gingrich retorted that “I will tell the truth, even if it's at the risk of causing some confusion sometimes with the timid.” – the “timid” reference an obvious poke at Romney.

There may be a theme in each of these responses. Gingrich is painting himself as the most experienced and knowledgeable – or at least the one with the longest history of dealing with major national and international issues, no matter how controversially.

And he got in a shot at Romney’s claiming not to be a career politician. "Let's be candid,” Gingrich said. “The only reason you didn't become a career politician is you lost to [Sen.] Teddy Kennedy in 1994. You'd have been a 17-year politician by now if you'd won.”

In the major Oops! Department, it was not the gaffe-prone Rick Perry who had some explaining to do but Romney, the one-time front-runner now scrambling to rise above third place in Iowa polling. (Ron Paul is second behind Gingrich.)

Clearly rankled by Perry’s repeated assertion that Romney had revised a portion of his book to soften his record on health care (and the despised individual mandate), the former Massachusetts governor thrust out his hand and challenged Perry to a $10,000 bet.

Perry declined the bet – wisely for a man who frequently mentions that he grew up without running water until he was six years old.

But for Romney, the damage had been done: He put himself squarely among what occupy wall streeters call the wealthy one percent.

“Romney, a millionaire 200 hundred times over, had the most out-of-touch moment in any debate so far,” said Democratic National Committee Chair Debbie Wasserman Schultz on the party’s website. The DNC helpfully pointed out that $10,000 equates to four months of pay for many American families or a year of mortgage payments for "the typical American home."

“Basic errors and bad moments are one thing. But when you make a mistake that reminds people of your greatest vulnerability, it can be a campaign killer,” wrote GOP strategist Mark McKinnon at Newsweek’s Daily Beast website.

Gingrich’s rivals will get one more chance before the Jan. 3 Iowa precinct caucuses to ding Gingrich and perhaps knock him off his first-place perch in the polls. There’s another debate Thursday night in Sioux City.

“My guess would be that from now on it’s trench warfare,” Drake University political science professor Dennis Goldford told IowaCaucus.com.