In the 1990s, Marianne Gingrich, Newt Gingrich's second wife, warned that she could give one interview about her Republican superstar husband and topple his career.

Whether the interview she gave ABC News derails a campaign gaining momentum remains to be seen.

But excerpts from her two-hour conversation with investigative reporter Brian Ross dominated the headlines Thursday, competing with Texas Gov. Rick Perry's bow out of the presidential race.

Perry's endorsement of Gingrich, as he conceded the contest for the Republican nomination, included the telling comment, "Newt's not perfect, but who among us is?"

In the interview, which was to air on ABC at 11:35 p.m., two days before the South Carolina primary, Marianne Gingrich talks of the moment when Gingrich revealed his six year affair with then-congressional aide Callista Bisek, conducted while he was still married to Marianne. She said her husband was clearly asking permission to continue the affair. “He wanted an open marriage, and I refused.”

Six months later Newt Gingrich married Bisek, and asked the Catholic Church for an annulment of his 18-year marriage to Marianne.

In an appearance on the ABC morning talk show "The View," Brian Ross commented that Marianne Gingrich does not think her ex-husband "has the moral character to serve as president, given what happened to her and what he asked of her."

During a campaign stop in South Carolina, Newt Gingrich said the interview was “tawdry and inappropriate,” and refused to answer any questions about it, according to The Washington Post. He also said: “I’m not going to say anything about Marianne."

Kathy Lubbers and Jackie Cushman, Gingrich's daughters from his first marriage to Jackie Battley, wrote a letter to ABC that was obtained by the website Politico, essentially asking that the details of his marriages be off-limits.

"The failure of a marriage is a terrible and emotional experience for everyone involved," they wrote. They also mention that parties in a divorce can have "differing memories of events. . . 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."

Marianne Ginther met Newt Gingrich in 1980 when he appeared at a fundraiser in Ohio. He asked her to marry him, she said, before he asked Battley for a divorce. That divorce took place in 1981 while the first Mrs. Gingrich was being treated for cancer.

Marianne mentions in her ABC interview that Gingrich asked her for a divorce shortly after she was diagnosed with multiple sclerosis.

During their bitter divorce proceedings, which played out over eight months in a Cobb County courtroom in 1999, a judge ordered Newt Gingrich to answer 32 questions posed by his estranged wife, according to a 1999 article in The Atlanta Constitution. At the time, she pressed him for details about extra-marital affairs predating Bisek.

One such question asked: "Do you believe that you conducted your private life in this marriage in accordance with the concept of ‘family values' you have espoused politically and professionally?"

Newt Gingrich answered all but one of the questions, according to another Atlanta Constitution article. It's unknown which one was skipped.

During the proceedings, Bisek was ordered to sit for a deposition with Marianne Gingrich's attorneys, but the divorce was finalized and sealed before the current-Mrs. Gingrich gave her testimony about the details of the affair.

Marianne and Newt Gingrich's marriage overlapped Newt's most dramatic years, during the carefully orchestrated Republican Revolution, his triumphant rise to become Speaker of the House in 1994,  and his rapid fall, when he resigned from Congress in 1998 under the pressure of ethics investigations.

The second Mrs. Gingrich, a resident of Marietta, has spoken very rarely of her ex-husband since their divorce. This is her first television interview of substance. She spoke at length with Esquire magazine in 2010, also criticizing him in that interview for campaigning on family values while conducting an extramarital affair.

According to Esquire, Newt's response was: "It doesn't matter what I do . . . People need to hear what I have to say."

Gingrich's lawyer, Randy Evans, of Vinings, who has worked on his campaigns since 1976, said the timing of the television interview demonstrates that "the elite media" is trying to control the outcome of the South Carolina primary.

Evans was contacted in Charleston as he waited in the hotel lobby before accompanying Gingrich to the televised debate. Evans represented Gingrich during his divorce from Marianne, and said the details of that break-up are old news.

"He's said it repeatedly," said Evans. "He acknowledges that he's made mistakes. He's had a road-to-Damascus moment. He's asked for forgiveness. He believes he's forgiven and he’s a different person today."

Evans said he didn't think the interview would have significant impact on the outcome in South Carolina. "The voters know all of this," he said. "You either believe in forgiveness or you don’t. If you believe in forgiveness and redemption, then you judge him for who he is."

Marianne Gingrich's attorney, John Mayoue, declined comment Thursday.

-- Staff writer Katie Leslie contributed to this report.