'Donald has a crowd size problem': Mary Trump says turnout issues will 'trigger' her uncle
U.S. President Donald Trump speaks at a rally on the Ellipse on Wednesday, Jan. 6, 2021, near the White House in Washington, D.C., shortly before his supporters stormed the U.S. Capitol. - Yuri Gripas/Abaca Press/TNS

Donald Trump's niece says that she's able to predict the ex-president's next "trigger" because she knows him so well.

Specifically, Mary Trump was referring to reports that, recently, the former president's rallies have lacked the vigor that they had in the past. She also pointed to Trump reportedly having "empty seats all over the arena."

"Donald isn’t going to like this," Mary Trump said Wednesday. "As he tries to grapple with Nikki Haley’s stronger-than-expected showing in New Hampshire, Donald’s campaign has a new problem: shrinking crowd sizes."

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Mary Trump said the crowd size issue might seem small to some but that, for her uncle, it is important.

"The appearance of low attendance has always been a trigger for Donald, who infamously lied about the crowd size of his inauguration," Mary Trump said. "If news of his crowd-size problem gets out, it will add to the increasing number of issues—like Nikki Haley’s stronger-than-expected showing, the increasing number of prominent politicians withholding their endorsements—having a negative impact on him."

She added some insider information based on her knowledge of the ex-president.

"The issue of crowd size may seem trivial, but not if you know Donald," she said on Wednesday. "Crowd size is one of the key ways Donald measures success. Small turnout, muted responses, and louder hecklers challenge him and stress him in a way few other things can. Huge crowds, and their violent energy, motivate him. They were a crutch. Without them, he loses an important method of deploying his message, and momentum."

Mary Trump concluded by suggesting that "Donald is vulnerable."

"We shouldn’t ignore it when New Hampshire Republican voters say they voted for Haley in order to stop Donald," she wrote. "Perhaps they are disgusted with his party too. Just this evening, the House ethics committee announced it reached out to a woman who allegedly had sex with Matt Gaetz when she was just 17 years-old."