"If they're so proud to stand shoulder to shoulder with KKK members and neo-Nazis then I think people should know their names," Smith said.
Smith who works as communications director for Progress NC Action, a left-leaning policy advocacy group in Raleigh, says he's "unmasked" about a dozen people so far. He said tips on the identities of the white nationalists have been coming in from across the country.
His Twitter following has skyrocketed from 65,000 to more than 300,000 and counting.
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But since Sunday, he said he's also been getting death threats.
"Making anti-Semitic threats, they've been telling me they're going to kill me, Smith said. "They've been threatening my family, even my extended family."
Smith said he has not published anyone's address, phone number or employer. He has reported the initial incidents of harassment and intimidation to Raleigh police.
He insisted he will not back down.
"This is how they operate," Smith said. "They want to keep people afraid."