Pennsylvania Republican Doug Mastriano accepted $500 from Andrew Torba, the CEO of Gab.
Torba is a self-styled Christian nationalist whose Gab website is favored by far-right extremists.
Mastriano paid Gab $5,000 to promote his campaign but later said Torba "doesn't speak for me."
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He has also said even conservative Jews are unwelcome, flatly stating, according to Media Matters: "We don't want people who are Jewish."