EXCLUSIVE: Rosie O'Donnell Is Certain Donald Trump 'Will Never Be President'

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Rosie O'Donnell strongly believes that Donald Trump doesn't have a chance at winning the White House.

"He will never be president," O'Donnell told ET's Carly Steel on opening night Tuesday of the Broadway musical comedy Disaster!.

When asked what she would do if Trump did manage to get voted in to office, O'Donnell refused to even entertain that hypothetical scenario, adamantly repeating, "He will never be president."

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O'Donnell, 53, and the 69-year-old GOP presidential hopeful have a long-standing feud, which has played out over the last decade in a series of public jabs and insults the two have leveled against each other.

Recently, Trump infamously mocked O'Donnell during the first GOP debate in August when asked by moderator Megyn Kelly about his history of making sexist and hateful comments toward women.

O'Donnell also briefly addressed her relationship with her 18-year-old daughter, Chelsea, telling ET, "My whole family is good."

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O'Donnell, an avid theater fan, then treated ET's camera to an impromptu performance of the song "Alexander Hamilton," the opening number from the wildly popular Broadway musical Hamilton.

"If I could go [see Hamilton] once a week, I would," said O'Donnell, who revealed that she has already seen it 14 times!

Check out the video below for more on Trump and O'Donnell's very public feud.

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