UPDATE: ABC News leaked excerpts of its much-anticipated interview with Marianna Gingrich, Newt Gingrich's estranged second wife. In the clips, Marianne says her husband lack the moral character to be president. He wanted an open marriage, and I refused, she told ABC's Brian Ross. The television interview -- Marianne's first since her marriage ended in 2000 -- will be broadcasted in full Thursday night on ABC at 11:35 PM E.T.

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Marianne Gingrich has rarely appeared in the public realm to talk about her husband, GOP hopeful Newt Gingrich, since their divorce. In the 1990s, she once said she could destroy his career with a single interview. In December 2010, she said he wasn't fit for president.

Just as he is picking up steam in the run for the Republican presidential nomination, Gingrich's second wife is back.

Reports surfaced Wednesday night that ABC News had scored a bombshell interview in which reporter Brian Ross sat down with the candidate's ex-wife for two hours. According to conservative news aggregator Matt Drudge, a civil war erupted in the news room about whether it would be unethical to run he interview before the South Carolina primary on Saturday.

The newsroom is going ahead with the report Thursday night on Nightline, to be aired after the CNN South Carolina debate, The Associated Press confirmed. ABC staffers told The Huffington Post they were surprised to hear about internal arguments, but The New York Times' cited a source who confirmed there was disagreement over the timing.  Gingrich's daughters, who have become the unofficial spokesmen of their family, were certainly worried enough to release a statement.

The failure of a marriage is a terrible and emotional experience for everyone involved,  Kathy Lubbers and Jackie Cushman said in a letter to ABC News execs, obtained by Politico.

ABC News or other campaigns may want to talk about the past, just days before an important primary election. But Newt is going  to talk to the people of South Carolina about the future.

Newt Gingrich himself dismissed the interview Thursday morning on the Today show, leaving it to Kathy and Jackie - daughters from his first wife - to talk about it.

I'm not going to say anything negative, Gingrich. I think the people who have known me a long time are credible on my characters.

How worried does Gingrich have to be? Depends how believable his wife is, because she likely won't be saying anything too nice about him. In an extensive interview with Esquire in 2010, she revealed the following juicy tidbits about Newt and more information about herself.

On their marriage: Gingrich proposed to Marianne in 1981, before his divorce with his first wife was finalized.  He asked me to marry him way too early. And he wasn't divorced yet. I should have known there was a problem, she told Esquire.

The two divorced in 2000, and Gingrich had admitted to having an affair with current wife Calista while he was still married to Marianne. After he returned from a speech in Erie, Pennsylvania about compassion and family values, she said, How do you give that speech and do what you're doing?

Newt maintains he no longer has a relationship with his second wife.

On his campaign: Marianne scoffed at the idea he was running for president. He believes that what he says in public and how he live don't have to be connected. If you believe that, then yeah, you can run for president.

On his financial skills: Marianne said she had to take over the family budget during their marriage because it was too stressful for him.

On her own politics: Although their relationship has gone way off the cliff, Marianne still supports her husband's politics. When they married, she was the daughter of a small-town Republican mayor. She supports the tea party.

On his Achilles heel:  Newt always wanted to be somebody, she told Esquire. That was his vulnerability, do you understand? Being treated important. Which means he was gonna associate with people who would stroke him, and were important themselves. And in that vulnerability, once you go down that path and it goes unchecked, you add to it. Like, 'Oh, I'm drinking, who cares?' Then you start being a little whore, 'cause that comes with drinking. That's what corruption is - when you're too exhausted, you're gonna go with your weakness. So when we see corruption, we shouldn't say, 'They're all corrupt.' Rather, we should say, 'At what point did you decide that? And why? Why were you vulnerable?'