WASHINGTON (AP) -- Being a conventional Republican has never been Newt Gingrich's style, and he clearly doesn't see it as the way to beat Mitt Romney in the presidential nominating contest.
Gingrich, the former House speaker, is sticking to his call for lenience for some illegal immigrants, a stand that critics call amnesty and that veers from GOP orthodoxy. A day after he emphasized his point in a debate, his position drew both praise and condemnation Wednesday.
But there's broader debate within Republican circles, six weeks ahead of the Iowa caucuses: Do party loyalists think their best challenger to President Barack Obama is a 68-year-old veteran of Washington's inside games, who left Congress with dismal approval ratings and who recently held a million-dollar consulting contract with mortgage backer Freddie Mac?
Gingrich is the latest Republican to emerge as a serious rival to Romney, the former Massachusetts governor who is more popular with the party establishment than with conservative activists. Campaign veterans still tend to see Romney as the likeliest nominee. But Gingrich's long, roller-coaster career makes it hard to rule him in or out with confidence.
Gingrich seems to have become "the center of gravity in this very unusual Republican nomination contest," said Dante Scala, a pollster and University of New Hampshire political scientist. He said the former Georgia congressman might be able to unite very conservative voters "who want a fundamental change in the scale and scope of government" and "somewhat conservative Republicans, who just want to defeat Obama."
"Illegal immigration is Newt's acid test," Scala said, and tea party conservatives might be "having second thoughts today. Let's see if he can keep them on board."
Attention focused Wednesday on Gingrich's renewed call for pathways to legal status for illegal immigrants who have lived long, peaceful and tax-paying lives in the United States.
"I don't see how the party that says it's the party of the family is going to adopt an immigration policy which destroys families which have been here a quarter-century," Gingrich said in the Republican debate Tuesday night. "I'm prepared to take the heat for saying let's be humane in enforcing the law."
Heat came quickly. "Newt Gingrich is finished!" said William Gheen, president of the anti-immigration group ALIPAC.
Rep. Steve King, R-Iowa, one of Congress' most outspoken conservatives, said Gingrich's prescription "is a form of amnesty" that "makes it harder" to consider endorsing him.
King told reporters America will suffer "if we let the rule of law be eroded and we allow people to be rewarded for breaking the law" by entering the country illegally.
Gingrich allies noted that he doesn't advocate citizenship, even for law-abiding, long-term illegal immigrants. They say his plan is a humane and realistic acknowledgment that the government is not going to round up and deport 11 million people who are here illegally. The smartest use of resources, they say, is to focus on illegal immigrants with few ties to their communities and problematic records with paying taxes and staying out of trouble.
Romney offered Gingrich no wiggle room. While campaigning in Iowa, he said, "People who have come to the country illegally should not have a special pathway that is preferable to those that stand in line in their home countries to come to this country."
Romney said Gingrich's plan would not stand scrutiny. "How about someone who's been here 20 years, how about 12 years, about 10, five, three?" he said. "How many children do you have to have to apply to this principle?"
"We make a mistake as a Republican Party in trying to describe which people who've come here illegally should be given amnesty," Romney said.
Democrats denounced Romney's position Wednesday. And some defended Gingrich, which may be of little help in Republican primaries.
"The truth is, he's correct," Rep. Charles Gonzales, the Texas Democrat who chairs the Congressional Hispanic Caucus, told reporters. "I'm hoping former Speaker Gingrich doesn't start walking back from it."
Steve Duprey, a Republican National Committee member from New Hampshire, who is uncommitted in the presidential race, said he applauds Gingrich for tackling the touchy immigration issue. "But he's going to have a problem with the conservatives," Duprey said
Some conservative journals are taking a wait-and-see approach to Gingrich's prospects.
"If 2012 were an ordinary election year, Gingrich would be doomed by his gaffes, three marriages and fleeting alliances with Hillary Clinton on health care and Nancy Pelosi on global warming," columnist Fred Barnes wrote in the Weekly Standard. But Republicans are obsessed with ousting President Barack Obama, he said.
"And if that means choosing a candidate with a lurid past and a penchant for self-destruction," Barnes said, then Republicans "are likely to swallow hard and nominate Gingrich."
Romney will keep arguing that he is best-suited instead.
Associated Press writers Thomas Beaumont in Iowa and Philip Elliott in Washington contributed to this report.