Marianne Gingrich, Newt Gingrich's ex-wife, is interviewed by ABC… (ABCNews.com )
Newt Gingrich asked for an "open marriage," his ex-wife says in a new interview being aired just 48 hours before South Carolina voters head to the polls (see video below).
Speaking with ABC News, Marianne Gingrich says that her then-husband made the request as he disclosed his six-year affair with a congressional staffer.
"I said to him, 'We've been married a long time.' And he said, 'Yes, but you want me all to yourself,' " Marianne Gingrich told the network.
She said her husband responded that the other woman "doesn't care what I do."
"He was asking to have an open marriage and I refused," she said. "That is not a marriage."
The other woman was Callista Bisek, who is now married to the GOP presidential hopeful.
According to excerpts released by ABC News, Marianne Gingrich describes the "shock" of learning of her husband's infidelity, which came at the same time he was condemning then-President Bill Clinton for his affair with a White House intern.
Gingrich moved to divorce her, she said, just after she was diagnosed with multiple sclerosis.
"He also was advised by the doctor when I was sitting there that I was not to be under stress. He knew," she said.
The full interview is set to air on ABC's "Nightline" on Thursday night, hours after another Republican candidates debate. South Carolina Republicans will vote in a presidential preference primary Saturday.
New polls show Gingrich has either substantially narrowed what had been a Mitt Romney lead, or taken an outright lead of his own.
The Gingrich campaign had no immediate reaction to the interview excerpts. Gingrich's daughters wrote a memo to ABC News executives Wednesday.
"We will not say anything negative about our father's ex-wife. He has said before, privately and publicly, that he regrets any pain he may have caused in the past to people he loves," Kathy Lubbers and Jackie Cushman wrote. "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 .... We are confident this is the conversation the people of South Carolina are interested in having."
In an interview on NBC's "Today" show Thursday morning, Gingrich declined to comment.
"I'm not going to say anything negative about Marianne," he said. "I realize that some of the elite media would like to do almost anything other than cover [President Obama's] failures, but the fact is ... we have a lot we can talk about today about real problems."