North Carolina Republican Sen. Thom Tillis, who is running for re-election, has become the fourth member of the Senate to test positive for COVID-19.

The senator announced Friday night that he has been diagnosed with coronavirus, making him the fourth member of the Senate and the sixth person who attended the nomination ceremony for Supreme Court justice candidate Amy Coney Barrett, to test positive for COVID-19.

“Over the last few months, I’ve been routinely tested for COVID-19, including testing negative last Saturday, but tonight my rapid antigen test came back positive,” Tillis said in a statement.