In a debate that started off with few differences from the night before, Mitt Romney's rivals pounded him once more on Sunday, looking for a chance to bruise the front-runner for the Republican presidential nominee.

Appearing in New Hampshire during a Sunday morning faceoff, just hours after the first bout in a doubleheader that began less than 12 hours earlier, the five other contestants in the GOP race took their turns pouncing on the former Massachusetts governor.

"If his record was so great as governor of Massachusetts, why didn't you run for reelection?" Rick Santorum asked Romney. "If it was that great, why did you bail out?" 

Santorum's question came after Romney fended off an attack from Newt Gingrich, who challenged Romney's record as not distinctive enough from President Obama to make him electable.

"I didn't go there to make a political career, time and time again," Romney said in response to the two-pronged attack, referencing his one term as governor. "Politics is not a career. For me, my career was in business. My life's passion has been my family, my faith and my country." 

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To that, Gingrich responded: "Can we drop a little of the pious baloney?"

The former House speaker said Romney tried and failed on several occasions to run for office, once against then-Sen. Ted Kennedy then in the 2008 presidential election.

Romney responded that he had no expectation that he'd win against Kennedy, but he stood up to fight to point to the problems he found with Kennedy's record when no one else would challenge the longtime senator, who died in 2009 while still a member of the Senate.

"You know there are a lot of people tuning in this morning and I'm sure they were terribly confused," said Jon Huntsman, the former Utah governor who served as President Obama's ambassador to China. "I was criticized by Romney for putting my country first." 

"I think we serve our country first by standing for people who believe in conservative principles and doing everything in our power to promote an agenda that does not include President Obama's agenda," Romney responded. 

As the candidates moved on, Rick Perry got his first laugh of the day, decisively answering a question asked Sunday of candidates other than him, but one which posed to him last summer began his slide in the polls. 

"Let me answer the question you asked earlier -- what are the areas that you would make some reductions that people would feel some pain?" Perry said. "And I will tell you, it would be those bureaucrats at Department of Commerce and Energy and Education."

The back-to-back debates come two days before New Hampshire voters go to the polls in the first-in-the-nation primary, which followed just one week after the Iowa caucuses, in which Romney bested Santorum by eight votes. Romney is far ahead in New Hampshire, where he has something of a home field advantage.

The remaining field to survive New Hampshire then head to South Carolina for the first-in-the-south primary on Jan. 21, which will be preceded by two more debates, including the Fox News debate on Jan. 16, sponsored by the Republican Party of South Carolina. Romney pointedly notes that he has been endorsed by South Carolina Gov. Nikki Haley.

Santorum, who is trying to find his footing in fiscally conservative New Hampshire after surging in socially conservative Iowa, also held no quiver against Ron Paul, who he accused of being unable to succeed as president because of a track record in Congress that demonstrated few successes in passing legislation.

Paul responded that his record demonstrates that Congress is too cumbersome and monolithic. He added that it's just now catching up to his warnings and prognostications.

On the issue of gay rights, in which several of the candidates have strongly denounced same-sex marriage, Santorum said that if he had a son who came to him saying he is gay, he would love him as much as the second before he told him so.

"Just because you disagree with someone's desire to change the law doesn't mean you hate them or want to discriminate him," Santorum said.

Romney too said he doesn't believe it's discriminatory against gay Americans to oppose same-sex marriage, Romney said he has a long record of inclusion, including having a gay man working in his administration while he was governor. Asked when is the last time he spoke up for gay rights, Romney responded, "Right now."