Nick Penzenstadler

USA TODAY

Donald Trump told the New York Times’ editorial board that his go-to applause line for sleepy crowds is about building a wall on the U.S.-Mexico border.

“You know, if it gets a little boring, if I see people starting to sort of, maybe thinking about leaving, I can sort of tell the audience, I just say, ‘We will build the wall!' and they go nuts.”

The newspaper used the quote in its editorial to ding both GOP frontrunners, Trump and Ted Cruz, calling them “equally objectionable for different reasons.”

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Trump’s proposal hasn’t come with a cost estimate. He says he would fund the project by forcing Mexico to pay for it by confiscating the wages earned by their undocumented immigrants in the U.S. and tripling the number of the nation’s deportation officers by eliminating some tax breaks they can currently claim.

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However, many of the new arrivals are Central Americans fleeing violence and extreme poverty. And many of them are turning themselves in to border guards, not evading them. Minus these asylum seekers and unaccompanied minors, the number of undocumented apprehended on the U.S.-Mexico border is at a 40-year low, according to the Migration Policy Institute.

A week ago, Trump made headlines by saying he is so popular, he could shoot someone and not lose voters. Addressing a campaign rally in Sioux Center, Iowa, he bragged that his "people" are the most loyal.

"I could stand in the middle of Fifth Avenue and shoot somebody and I wouldn't lose any voters, okay? It's, like, incredible," Trump said.

Trump: I could shoot a person and not lose votes