House Speaker Nancy Pelosi, D-Calif., said she worries that President Trump might not give up power if he is defeated in 2020.

“We have to inoculate against that, we have to be prepared for that,” she told the New York Times.

Pelosi said Democrats need to defeat Trump by a margin so big that he can’t question the legitimacy of the election. The speaker said she worried before the 2018 midterm elections, in which Democrats picked up 40 seats, that if Democrats didn’t perform as well that Trump might have disputed control of the House.

“If we win by four seats, by a thousand votes each, he’s not going to respect the election,” she recalled. “He would poison the public mind. He would challenge each of the races; he would say you can’t seat these people.”

“We had to win. Imagine if we hadn’t won — oh, don’t even imagine. So, as we go forward, we have to have the same approach,” Pelosi added.

She also said that Democrats shouldn’t indulge the “other exuberances” of some in the far-left of her party but should rather focus on appealing to the mainstream in a bid to unseat Trump.

“Own the center-left, own the mainstream,” she said.

Pelosi has pushed back on some of the more progressive members of her party who are calling for a Green New Deal and “Medicare for all.” She has also publicly rebuffed calls for Trump’s impeachment, despite other members in her party calling for impeachment proceedings to begin.

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