Even many of Trump's supporters shook their heads at his latest outburst, which could further hurt him among the nation's women, many of them already skeptical, whose votes he'll badly need to win election.
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"Did Crooked Hillary help disgusting (check out sex tape and past) Alicia M become a U.S. citizen so she could use her in the debate?" read a missive from Trump posted on Twitter at 5:30 a.m. That referred to 1996 Miss Universe winner Alicia Machado, a Venezuela-born woman whose weight gain he has said created terrible problems for the pageant he formerly owned.
Did Crooked Hillary help disgusting (check out sex tape and past) Alicia M become a U.S. citizen so she could use her in the debate?— Donald J. Trump (@realDonaldTrump) September 30, 2016
Unsurprisingly, Trump's pre-dawn tweet-storm ricocheted across the campaign trail.
Trump's campaign accused the media and Hillary Clinton of colluding to set him up for fresh condemnation, to which Clinton retorted, "His latest twitter meltdown is unhinged, even for him."
Machado took to Facebook to say his tweets were part of a pattern of "demoralizing women," calling them "cheap lies with bad intentions." Planned Parenthood said it showed that Trump's "misogyny knows no bounds." And Clinton said they showed anew why someone with Trump's temperament "should not be anywhere near the nuclear codes."
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With less than 40 days left in the election, Trump's broadside threw his campaign into a fresh round of second-guessing the candidate's instincts and confusion about what to do next. To believers in traditional political norms, the tirade seemed like the opposite of what was needed to win over females, Hispanics and young Americans whose support could well determine the election.
Shaming Machado over intimate details from her past could be particularly risky as Trump tries to win over more female voters, many of whom are turned away by such personal attacks. It also risks calling further attention to the thrice-married Trump's own history with women.
Charges of lying flew back and forth.
What kind of a man, Clinton asked, "stays up all night to smear a woman with lies and conspiracy theories?"
Trump implored voters not to believe news stories about his campaign citing anonymous sources. "There are no sources, they are just made up lies!" he tweeted.
Yet even Trump's most vocal allies seemed at a loss for words.
READ MORE: Clinton describes Trum's latest Twitter 'meltdown' as 'unhinged'
"He's being Trump. I don't have any comment beyond that," said former House Speaker Newt Gingrich, a top supporter. Generally chatty and occasionally critical of Trump, Gingrich said tersely that Trump sometimes does "strange things," but that Clinton lies. "I'll let you decide which is worse for America."
But Trump's inner circle followed his lead by refusing to concede any missteps. Trump didn't mention the tweets Friday evening as he rallied supporters in Michigan. Instead, he returned to Twitter to invoke Clinton's famous ad from her 2008 campaign portraying her as the best candidate to pick up an urgent call at the White House at 3 a.m.
"For those few people knocking me for tweeting at three o'clock in the morning, at least you know I will be there, awake, to answer the call!" Trump wrote.
Machado has been thrust to center stage in the campaign since Clinton noted Monday in the first debate that Trump had mocked her publicly for gaining weight after she won Miss Universe. If that was a trap laid by Clinton, the irrepressible Trump dug himself deeper the next day by saying Machado's "massive" weight gain had been "a real problem."
That gave Clinton's campaign the opening it wanted. Her team circulated videos featuring Machado accusing Trump of destroying her self-confidence and arranged for reporters to interview her, just as many voters were starting to cast early ballots. Clinton's spokesman said she called Machado Friday to thank her for her courage.
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Said Trump spokeswoman Jessica Ditto: "This is the single biggest coordinated media attack in history."
His Twitter taunts referred to footage from a Spanish reality show in 2005 in which Machado was a contestant and appeared on camera in bed with a male contestant. The images are grainy and do not include nudity, though Machado later acknowledged in the Hispanic media that she was having sex in the video.
Clinton's campaign has highlighted Machado's status as a new U.S. citizen and her plans to cast her first vote for the former secretary of state. But spokeswoman Jennifer Palmieri said Clinton did not help Machado become a citizen.
For those few people knocking me for tweeting at three o'clock in the morning, at least you know I will be there, awake, to answer the call!— Donald J. Trump (@realDonaldTrump) September 30, 2016
For Republicans, the outburst seemed to foreclose any possibility that Trump, in the campaign's final weeks, might reinvent himself as someone with the discipline and restraint that many voters want in their commander in chief. Trump's allies have implored him to stick to attacks on Clinton's family foundation, her emails or her long history as a political insider, critiques that fall further out of view whenever he sparks a new controversy.
In another risky move, Trump warned voters this week that a Clinton victory would bring former President Bill Clinton's sex scandal back to the White House. The fresh rehash of the 1990s Monica Lewisnky scandal came despite Trump's insistence that he's been courageously restrained in not bringing it up.
The presidential debate began at 6 p.m. on ABC7. For full coverage on the presidential election, click here.
Wow, Crooked Hillary was duped and used by my worst Miss U. Hillary floated her as an "angel" without checking her past, which is terrible!— Donald J. Trump (@realDonaldTrump) September 30, 2016
Using Alicia M in the debate as a paragon of virtue just shows that Crooked Hillary suffers from BAD JUDGEMENT! Hillary was set up by a con.— Donald J. Trump (@realDonaldTrump) September 30, 2016