The most vibrant episode of tonight's Republican debate happened at the very beginning, as Newt Gingrich dismissed an explosive interview given by his ex-wife and accused the mainstream media of shielding President Obama.
CNN moderator John King opened the forum by asking Gingrich about an interview that his ex-wife Marianne Gingrich gave to ABC News, in which she said the former House speaker wanted an "open marriage" with her in 1999. Gingrich turned the question around on King, blaming the mainstream media for detracting from the issues and earning a standing ovation from the audience.
"I think the destructive, vicious, negative nature of much of the news media makes it harder to govern this country, harder to attract decent people to run for public office, and I am appalled that you would begin a presidential debate with a topic like that," Gingrich said to cheers.
"Every person in here knows personal pain. Every person in here has had someone close to them go through painful things. To take an ex-wife and make it two days before the primary, a significant question in a presidential campaign, is as close to despicable as anything I can imagine."
As King tried to point out that CNN wasn't responsible for the interview, Gingrich jumped in and said that "it was repeated by your network."
"You chose to start the debate with it," he said. "Don't try to blame it on somebody else."
Gingrich, 68, has won support from Republican audiences by being openly skeptical of the media. In tonight's debate, he triumphed as he said, "I am tired of the elite media protecting Barack Obama by attacking the public."
The other candidates -- only three others, now -- were asked if the matter was a valid campaign issue. Mitt Romney, the front-runner in the race, said simply, "let's get on to the real issues."
Rick Santorum, though, said that "these are issues of our lives" and that "those are things for everyone in this audience to look at."
The spotlight quickly turned to Romney, though, as he was pressed on his tenure at Bain Capital, but more aggressively his decision not to release his tax returns just yet.
Romney, 64, was booed as he was asked whether he would release his tax returns for multiple years, as his father did. "Maybe. I don't know how many years I'll release," he said before a few people in the audience began to heckle him and boo.
"And I'll release multiple years. I don't know how many years, but I'll be happy to do that," he said.
Romney also argued that he should release his taxes at once instead of "drip by drip," so that Democrats don't "go out with another array of attacks" each time.
Romney told reporters this week that he pays a 15 percent tax rate, a figure that is lower than what most Americans pay because most of his income comes from investments, not a salary. But at the debate in South Carolina, Romney said, "I pay a lot of taxes."
"I'm honest in my dealings with people," he said. "My taxes are carefully managed."
Gingrich's camp, meanwhile, released his tax returns online during the debate.
In the center of the stage with the front-runner, Gingrich tried to close the gap with Romney by citing his deficiencies. But Romney came to the debate prepared.
In a portion of the debate about the economy, Romney tried to disarm Gingrich by arguing that the former House speaker didn't have as big of a role in creating jobs during Congress as he has claimed. Romney's secret weapon was the diary of Ronald Reagan, the hero of the Republican Party.
"I looked at the Reagan diary. You're mentioned once in Ronald Reagan's diary," Romney said. "And in his diary, he says you had an idea in a meeting of young congressmen, and it wasn't even a very good idea."
Gingrich fired back later in the debate by trying to trap Romney on his positions on abortion, an issue that a so-called super PAC supporting Gingrich has raised in South Carolina in an effort to sway religious voters. Gingrich cited a litany of provisions in Romney's Massachusetts health care law that he said allowed tax-funded abortions, even after Romney had supposedly adopted an anti-abortion stance.
"If you're genuinely pro-life, how come these things are appearing?" Gingrich said.
Romney's response was that he's a "pro-life individual" whose integrity shouldn't be questioned.
The candidates also got heated while discussing health care, an issue that has taken a back seat to other matters during the campaign. Santorum led the charge against Romney as he lambasted "RomneyCare" for being the starting point for Obama's health care program that is hated among many Republicans.
Bluntly, Santorum, 53, said Romney's health care plan that was put in place in Massachusetts was the model that Obama used.
"He's going to have run against a president who's going to say: 'Well, look. Look at what you did for Massachusetts, and you're the one criticizing me? ... I used your model for it.'"
While the crowd responded warmly, signaling many conservatives' hesitance to embrace Romney, the former Massachusetts governor said his plan was "absolutely not" perfect but that "having been there, having been on the front lines," he'd know how to repeal Obama's plan.
Santorum didn't buy it. "You do not draw a distinction that's going to be effective for us, just because it was at the state level, not the federal level," he said.
But Santorum also didn't save his criticism just for Romney. He accused Gingrich of being late to back off his stance on the individual mandate, and he later argued that Gingrich would be a dangerous Republican nominee because he's unpredictable. As an example, Santorum cited Gingrich's comment that Santorum should drop out of the GOP race, even though the former Pennsylvania senator beat him in Iowa and in New Hampshire.
"These are not cogent thoughts," Santorum said, adding that he feared a "worrisome moment that something's going to pop, and we can't afford that in a nominee."
"I'm steady. I'm solid. I'm not going to go out and do things that you're going to worry about," Santorum said.
The candidates also debated economic proposals, and with it, the focus on Romney's tenure at Bain Capital.
Romney has been criticized by Democrats and some GOP candidates alike for his role at Bain, being portrayed as a corporate raider who profited while people lost their jobs at companies in which the private-equity firm invested.
Romney has defended his time there by saying that four major companies that Bain helped have created more than 100,000 jobs, including 10,000 jobs that were lost.
"Capitalism works. Free enterprise works," Romney said at the South Carolina debate, adding that it felt "kind of strange on a stage like this with Republicans having to explain" how private equity and capitalism works.
Gingrich, who is gaining on Romney's lead in South Carolina, took a local angle as he tried to highlight Romney's time at Bain, saying that the company Georgetown Steel was hurt.
"He cited his experience as a key part of his preparation for being president," Gingrich said. "Those cases ought to be looked at."
Thursday night's debate did see a new topic: SOPA, or the anti-piracy bill that has drawn outrage from Internet users who say that it would unfairly censor websites, and which got a swarm of media attention this week as popular sites went dark in protest.
The mere mention of the topic drew boos from the crowd, and, perhaps not surprisingly, all of the candidates said they opposed the bill. Rep. Ron Paul, who has championed the effort to kill the proposal, said he was glad the other candidates disapproved of it, because "Republicans have unfortunately been on the wrong side of this issue."
Paul, 76, repeatedly clamored for attention, particularly on health care and on abortion (he's a doctor). His supporters in the audience boosted him, too, after three candidates exchanged views on abortion and King tried to move on, they screamed "Paul" until the moderator engaged the libertarian.
One topic that Paul was not eager to talk about was his taxes: He admitted that he has "no intention" of releasing financial documents, because, he said, he'd be "embarrassed" to have his lower income compared with the rest of the candidates.
"I think you know more about me than I know about myself," he said.
By far, as has happened in most of the dozen-and-a-half debates, Gingrich won the most applause throughout. He did it with lines like this: "Elect us and your kids will be able to move out because they'll have work."