The former House speaker weighed in during an exchange on illegal immigration and border security during Tuesday night's national security-focused debate on CNN.
"I do not believe that the people of the United States are going to take people who’ve been here for a quarter of a century ... [and] separate them from their families and expel them," Gingrich said. "I do believe we should control the border. I do believe we should have very severe penalties."
He continued, "I don't believe that the party that says it's the party of the family is going to say it’s going to destroy families that have been here for more than a quarter of a century. I'm prepared to take the heat in saying: Let's be humane in enforcing the law."
Minnesota Rep. Michele Bachmann immediately seized on the statement.
"Well, I don't agree that you would make 11 million workers legal, because that in effect is amnesty," she said. "And I also don't agree that you would give the Dream Act on a federal level. And those are two things that I believe that the speaker had been for."
The Romney campaign came down hard on Gingrich, while taking a shot at another Republican who's taken heat on the immigration issue.
"I think Newt Gingrich is closer to Rick Perry than he is to Mitt Romney," Eric Fehrnstrom, a spokesman for the former Massachusetts governor, told reporters after the debate. "He supported the 1986 amnesty, and even though he concedes it was a mistake he's willing to repeat that mistake by granting amnesty to people who are today in the country illegally."
Romney, Fehrnstrom said, "opposes amnesty, he opposes in-state tuition benefits for illegal immigrants, he wants to put in place a strong employer-verification system with penalties for companies that hire illegal immigrants."
R.C. Hammond, a Gingrich spokesman, countered that Gingrich's position was being distorted.
"Newt is for the idea of a local community review board, where citizens can decide whether or not their neighbors who have come here illegally should find a path to legality -- not citizenship, which is two different things," he told reporters.
The exchange on immigration was just one of the flashpoints in Tuesday's debate.
Earlier in the debate, Gingrich on the offensive, berating Texas Rep. Ron Paul for saying he would do away with the Patriot Act, which the Texas congressman had called "unpatriotic" and a threat to individual liberty.
"I'd look at strengthening [the Patriot Act] because I think the dangers are literally that great," Gingrich said.
"That is unpatriotic because it undermines our liberty," Paul responded. "Terrorism still on the books, internationally and nationally, is a criminal -- it's a crime, and we should deal with it. We dealt with it rather well with Timothy McVeigh."
"Timothy McVeigh succeeded," Gingrich fired back. "That's the whole point. ... I want a law that says you try to take out an American city, we're going to stop you."
U.S. policy in Afghanistan and Pakistan was the subject of another round of sparring between the candidates.
Bachmann called Perry "highly naive" for saying he would cut off aid to Pakistan, which the Texas governor advocated because Pakistan had shown the world that "they can't be trusted."
"And until Pakistan clearly shows that they have America's best interests in mind, I would not send them one penny, period," Perry said.
Bachmann, a member of the House Intelligence Committee, said in response that you "have to recognize what's happening on the ground."
"They certainly aren't looking out for the best interests of the United States. I wouldn't expect them to. But at the same time we have to have our interest, which is national security, represented," she said. "The best way we can do that with an uneven actor state is to have some sort of presence there."
Romney agreed, and defended a robust military presence in Afghanistan as well to ensure that it does not become a "launching point for terror."
Jon Huntsman, the former Utah governor, said the United States had achieved some major goals there, and needed to draw down its military presence.
"We haven't done a very good job defining and articulating what the end point is in Afghanistan," he said. "I think the American people are getting very tired about where we find ourselves today."
Romney said he would listen to the advice of commanders on the ground. Huntsman replied, "The president of the United States is commander in chief."
Economic issues have dominated the Republican race for president, but with polls showing that no candidate has yet established a consistent, substantial lead, the issues raised Tuesday could further shake up the race.
The Republican candidates won't meet again for a debate until Dec. 10 in Iowa.
Kim Geiger contributed to this report.