The Democratic nominee said "you could just sense how much anger he had" during her first interview since the debate.
Hillary Clinton says Donald Trump "stalked her" at Sunday's debate because he was seething over the release of the "Access Hollywood" tape.
In a sit-down on "The Ellen Show" set to air Friday, the candidate's first interview since the debate, Clinton tells DeGeneres that Trump's fury was palpable as he stood behind her in St. Louis.
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"Because of the revelation of the public video, and everything that came out on 'Access Hollywood,' you know, he was really all wrought up, and you could just sense how much anger he had,” Clinton said.
That anger, Clinton argued, stemmed from the profanity-filled tape on which Trump can be heard bragging to TV personality Billy Bush about his ability to grab women "by the p****" without asking, thanks to his stardom.
Fallout from the release of the 2005 recording was swift as Trump was immediately assailed both from his detractors and from members of his own party.
Clinton believes Trump's anger over the campaign-crippling controversy translated to a puffed-up presence on debate night.
"He was really trying to dominate and then literally stalk me around the stage," she told DeGeneres.
Clinton continued:
"It was so odd, because I’d go to talk to somebody and I would just feel this presence behind me, and you know, I thought, 'Whoa this is really weird.'"
Trump was accused of apparently trying to intimidate Clinton in the hours and days after Sunday's town hall-style faceoff, accusations Trump responded to at a campaign stop Monday.
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"So, I'm standing at my podium by my chair. She walks across the room. She's standing in front of me, right next to me. And the next day I said what did the paper say? They said, 'he invaded her space.'"
"Believe me," Trump said, "The last space that I want to invade is her space. Believe me. I don't want to invade her space."