(CNN) Illinois GOP Gov. Bruce Rauner encouraged people to "vote for anyone but" the Holocaust denier who's running for the state's 3rd Congressional District as a Republican, after declining Tuesday to endorse his Democratic opponent.

Arthur Jones, a former leader of the American Nazi Party, ran uncontested to be the Republican candidate in the Chicago-area district. His campaign website includes a section titled "Holocaust?" Jones has been involved with anti-Semitic and racist groups since the 1970s, according to the Anti-Defamation League, though he told CNN's Alisyn Camerota earlier this year that he is no longer formally involved with the Nazi party.

"No," he said in response to a question about whether he would endorse Lipinski, according to WCIA. "The one thing I will say is the person, that guy, Johnson or whatever his name is, should not be on the ballot."

Sen. Ted Cruz, a Texas Republican, had encouraged Illinois voters to "write in another candidate, or vote for the Democrat" in a tweet on Friday.

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