By Jeremy Diamond CNN

WARNING: This story contains graphic language.

Donald Trump apologized early Saturday for lewd and sexually aggressive remarks he made a decade ago -- and then made it clear he is girding himself for a nasty political battle.

The GOP presidential nominee posted a defiant 90-second video just after midnight on social media, telling voters that he is not a "perfect person" and that the words captured by a hot mic in 2005 "don't reflect who I am."

"I said it, I was wrong and I apologize," Trump said of footage from a previously unaired taping of "Access Hollywood" that surfaced Friday, in which Trump bragged about being able to grope women because of his "star" status.

But Trump quickly pivoted back onto the attack, raising Bill Clinton's sex scandals and Hillary Clinton's role in discrediting women who had affairs with her husband.

"I've said some foolish things, but there's a big difference between the words and actions of other people. Bill Clinton has actually abused women and Hillary has bullied, attacked, shamed and intimidated his victims."

And in closing, Trump added ominously: "We will discuss this more in the coming days. See you at the debate on Sunday."

While Trump refuted the lewd terms in which he discussed women in the 2005 tape, the Republican nominee did not apologize for or address the behavior he said in that conversation that he engaged in toward women, including that he would sometimes "just start kissing them."

Trump's foreshadowing that he will raise Bill Clinton's affairs and sex abuse allegations from the 1990s "in the coming days" suggest that the Republican nominee is switching gears after suggesting as recently as Thursday night that he would not raise those scandals in the debate on Sunday.

"I think we're all better off if we can do that," Trump said at a town hall event in New Hampshire on Thursday night.

But the bombshell 2005 recording has now put Trump on his heels -- with Republicans warning of his demise -- and the brash billionaire appears prepared to do what he does best: punch back.

Shocking remarks

Trump is heard discussing women in vulgar terms during off-camera banter during the taping of a segment for "Access Hollywood," footage which was obtained by The Washington Post.

During the lewd conversation captured by a microphone Trump was wearing on his lapel, Trump recounts bragging that he is "automatically attracted to beautiful (women)" and just starts "kissing them."

"Access Hollywood" later identified the unidentified woman as Nancy O'Dell, who used to work for the show. CNN has attempted to contact O'Dell's manager but has not heard back.

In the video, Trump uses the name "Nancy."

The conversation came months after Trump married his third and current wife, Melania.

He also said: "When you're a star, they let you do it. You can do anything."

The jaw-dropping description of uninhibited sexual assault as a benefit of his celebrity poses a substantial setback to Trump's attempts to overcome his deficit with female voters with just a month until Election Day. Clinton and her campaign have repeatedly sought to portray Trump as disrespectful and demeaning toward women, bringing up a slew of rude and vulgar comments Trump has made about women during and before his run for president.

House Speaker Paul Ryan, saying he was "sickened" by Trump's comments, announced Friday night that the GOP presidential nominee would no longer attend a Republican event in Wisconsin at which the two were slated to appear on Saturday. Multiple sources told CNN that Trump was asked not to come by Ryan, and one source said the message was delivered via intermediaries.

Trump's campaign said vice presidential nominee Mike Pence would represent him instead while the real estate magnate focuses on debate prep.

Trump campaign advisers were huddling together in Trump Tower Friday night trying to figure out how to react. Among the options being considered was whether Trump should make a public appearance Friday night.

Stakes raised for debate

The comments immediately raised the stakes for Sunday's highly anticipated debate between Trump and Clinton, and the remarks could hand her -- and viewers in the town hall audience -- more evidence to make that point.

And the remarks prompted Trump -- for the first time in his nearly 16-month campaign -- to apologize.

"This was locker room banter, a private conversation that took place many years ago. Bill Clinton has said far worse to me on the golf course - not even close. I apologize if anyone was offended," Trump said in a statement released Friday.

Clinton's campaign tweeted a link to the story and said simply, "This is horrific. We cannot allow this man to become president."

Democratic vice presidential nominee Tim Kaine, campaigning in Las Vegas, said Trump's comments "makes me sick to my stomach."

"I don't like to say the words that he's used in the past when he calls women, 'pigs, dogs and slobs' ... but this is behavior that's just outrageous and so that there would be a news story that would have more statements like this of this kind, I mean, gosh, I'm sad to say that I'm not surprised," Kaine said. "I should be surprised and shocked. I'm sad to say that I'm not."

A Clinton campaign source told CNN the campaign strategy in the wake of the tape will be to press Republicans to say if they still think Trump should be president.

"Not just condemn what he said -- but that he should be POTUS," the source said.

Two people close to the campaign told CNN the former secretary of state was unlikely to speak about the controversy Friday night. But it has become a new subject of her debate prep, and the campaign will pressure Ryan and other Republicans to disavow Trump throughout the weekend.

'You can do anything'

The hot mic conversation captured in 2005 begins with Trump recounting to "Access Hollywood" host Billy Bush how he tried to have sex with a married woman.

"I moved on her and I failed. I'll admit it," Trump says in the newly-released audio. "She was married."

"I moved on her... but I couldn't get there. And she was married," Trump adds, after saying he took the woman -- who is identified only by her first name -- out furniture shopping.

"Then all of a sudden I see her, she's now got the big phony tits and everything. She's totally changed her look," Trump says of the woman.

The conversation took place as Trump arrived in a tour bus on the set of "Days of Our Lives," the soap opera where he was set to make a cameo appearance.

Before Trump stepped off the bus, he and Bush appear to see an actress from the soap opera who greets Trump and Bush.

"Whoa!" Trump says. "I've gotta use some tic tacs, just in case I start kissing her. You know I'm automatically attracted to beautiful -- I just start kissing them. It's like a magnet. Just kiss. I don't even wait."

"And when you're a star, they let you do it. You can do anything," Trump says.

"Whatever you want," says another voice.

Priebus condemns remarks

Republican National Committee Chairman Reince Priebus condemned Trump's remark in a briefly, tersely-worded statement.

"No woman should ever be described in these terms or talked about in this manner. Ever," Priebus wrote.

Journalists covering a Toledo, Ohio, campaign stop by Pence were ushered out of a restaurant soon after the story broke. The press was supposed to cover Pence looking at a wall of signed hot dogs, including one by Trump, but were later told they couldn't record the moment.

A campaign staffer later told CNN the decision had "nothing to do with the news."

Pence declined to answer a question about the matter when asked by a reporter following a campaign event in Rossford, Ohio.

Some of Trump's old political foes rushed to slam the GOP nominee.

"As the grandfather of two precious girls, I find that no apology can excuse away Donald Trump's reprehensible comments degrading women," Jeb Bush tweeted.

"Hitting on married women? Condoning assault? Such vile degradations demean our wives and daughters and corrupt America's face to the world," Mitt Romney said on Twitter.

"Make no mistake the comments were wrong and offensive. They are indefensible," John Kasich added.

Former Utah Gov. Jon Huntsman, a Republican who recently said he would vote for Trump, called for Trump to drop out of the race.

Utah Gov. Gary Herbert, who over the summer had said he would vote for Trump, withdrew his support Friday night. So did House Oversight Committee Chairman Jason Chaffetz, a Utah Republican.

Even Terry Gainer, a former US Senate sergeant at arms who rarely makes political comments, emailed CNN to say, "It is not just woman who should shun Trump. Any gentleman, every husband, each father of a daughter, bother of a sister and sons must be outraged.

"How do I explain this to my granddaughters? If only a Republican leader would stand and exhibit a profile in courage."

Staffers shocked

Reactions from GOP staffers and advisers to Trump ranged from astonished to apoplectic.

A close adviser to Trump told CNN the story is "flat out appalling" and at this point, they can't even begin to guess whether Trump can come back from this.

"This should have never happened. I wish it had never happened. I think I know that men talk this way sometimes, but it's nothing I would ever want to hear or condone or approve of," the adviser said. "My reaction is -- it's appalling. It's just flat out appalling."

The adviser also said Trump's apology does not go far enough.

"Doing anything other than to say it was a grievous error and he apologizes would be a mistake," the adviser said. "I would take it a step further and own to the words as being offensive -- not 'if.'"

The adviser, clearly exasperated, added: "Another day in Trump world ... I hate it."

Asked about the reaction at a campaign field office, a Trump field staffer told CNN there were "gasps. Collective gasps. We're trying to get our heads around it right now, but there's no way to spin this. There just isn't."

The staffer, who is also paying close attention to Senate efforts, also added, unsolicited: "Just think of the down-ballot effect. Brutal."

A GOP operative in Ohio voiced similar sentiments.

"This is bad. I think this thing is over," the staffer said.

Reached for comment, a top battleground state staffer told CNN he was "picking (his) chin off the floor."

"We want every suburban woman's vote in America. This doesn't help with that," the staffer said.

And a Trump campaign source said they were "dumbfounded," saying the remarks "could be a death knell."

The source had no predictions on how the article will impact the race, saying the next two days will be critical.

"I think the next 48 hours will be the most consequential of the entire election. Right here, right now, this is game time," the source said.

One senior Trump adviser said simply, "Ugh."

A stunning apology

The seriousness of Trump's remarks could be gauged by his apology, the first time he has offered such a concession as a presidential candidate. He has offered "regret" on several occasions, notably in August when he acknowledged he sometimes says "the wrong thing" and in April when he said retweeting an unflattering picture of Ted Cruz's wife, Heidi Cruz, was "a mistake."

Previously, Trump has said that he would only apologize for something if he was "wrong."

"I fully think apologizing is a great thing. But you have to be wrong," Trump said in a September 2015 appearance on "The Tonight Show."

And in a March CNN town hall, Trump could not recount the last time he had apologized for something but said that "if you're not wrong, I don't believe in apologizing."

Pressed again on specific times when he's apologized for anything in his life.

"Yes, I mean -- apologized -- I apologized to my mother years ago for using foul language," Trump said. "I apologize to my wife for not being presidential on occasion."

Trump and women

Trump has repeatedly bragged that "nobody respects women more" than him and has vowed to "cherish" and "protect" women as president.

But the newly unearthed recording is just the latest revelation that shows the crude and at-times sexist terms Trump has used to describe women.

During his run for president, Trump suggested that his GOP primary opponent Carly Fiorina, a former Fortune 500 CEO, was too ugly to be elected president, shouting "look at that face! Would anyone vote for that?" during an interview with Rolling Stone magazine. And Trump also suggested that Fox News anchor Megyn Kelly asked him tough questions during the first GOP debate because she was on her period, saying there was "blood coming out of her wherever."

Trump most recently stoked controversy after he defended his belief that former Miss Universe Alicia Machado had "gained a massive amount of weight and it was a real problem." He was also accused of calling her "Miss Piggy" back in the 1990s.

In his numerous appearances on "The Howard Stern Show," Trump also frequently engaged the show's host in lewd and objectifying conversations about women, including discussing his sexual encounters.

Trump on the show frequently ranked women on a scale of 1 to 10 and discussed everything from oral sex to anal sex to whether he could get an erection for certain famous women.

"A person who is flat-chested is very hard to be a 10," Trump said in one segment with Stern.

Discussing a famous actress's recent breast augmentation, Trump said: "The boob job is terrible, you know they look like two light posts coming out of a body."

Trump most recently defended some of the crude comments he has made about women by telling local Las Vegas news station KSNV that "a lot of that was done for the purposes of entertainment."

"There's nobody that has more respect for women than I do," Trump said.

CNN's MJ Lee, Phil Mattingly, Gloria Borger, Jeff Zeleny, Jason Caroll, Jim Acosta, Dana Bash, Ashley Killough and Elizabeth Landers contributed to this report.

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