WASHINGTON – Former Massachusetts Gov. Bill Weld, who is a longshot challenger to President Donald Trump for the 2020 Republican nomination, this week called the president a "raging racist," adding that if Republicans don't denounce Trump in the upcoming election they will be known as the "party of racism."

"Donald Trump is a raging racist, Okay? He's a complete and thoroughgoing racist," Weld said Wednesday during the national NAACP convention in Detroit. "And he made that choice, a choice a long time ago, when he was engaged in the housing business in New York with his father."

Trump earlier this month tweeted that four Democratic congresswomen of color should "go back" to their countries. Reps. Alexandria Ocasio-Cortez of New York, Ayanna Pressley of Massachusetts, Ilhan Omar of Minnesota and Rashida Tlaib of Michigan have all rebuked Trump's comments as racist. The House of Representatives also formally condemned the president's tweets as racist.

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Since his initial online postings, the president has repeatedly doubled down on his comments and attacks on the four Democrats. During a North Carolina rally on July 17, chants of "send her back" broke out when Trump began criticizing Omar.

All four congresswomen are U.S. citizens and three were born in the U.S. Omar immigrated to the U.S. from Somalia over 20 years ago and is naturalized citizen.

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Weld warned the Republican Party that if it does not denounce Trump in 2020, the GOP will be known as the "party of racism in America."

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"The national Republican Party has a choice. And a lot of them like to think that it's a political choice," he said. "But it's not a political choice. It's a moral choice."

"Unless the Republican Party in Washington expressly, expressly rejects the racism of Donald Trump, they're going to come to be universally viewed as the party of racism in America," he concluded.

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