Sen. Ron Johnson tests positive for coronavirus.

Wisconsin Sen. Ron Johnson is the third Republican senator to test positive for coronavirus.

Unlike Sens. Mike Lee and Thom Tillis, Johnson was not at the White House last Saturday for Amy Coney Barrett’s nomination ceremony.

It is unclear where Johnson contracted the virus, but he was exposed earlier this week to someone who has since tested positive for the virus, according to his office. 

“Senator Johnson feels healthy and is not experiencing symptoms. He will remain isolated until given the all-clear by his doctor,” a spokesperson for Johnson. “Most staff in the senator’s Washington office have been working remotely. The office will go all-virtual for the immediate future.”

With three Republican senators testing positive for the virus, it’s places Judge Amy Coney Barrett’s nomination to the high court in jeopardy. The Senate Judiciary Committe is expected start hearings on October 15.

Chairman Lindsey Graham needs to have nine total members of the committee present, including two Democratic members, to officially consider the nomination.

Democrats could boycott this meeting, thereby preventing Graham and the Republicans from reaching a quorum.

To approve the nomination, the committee rules require a majority of members to be present. There are 12 Republicans and 10 Democrats, so if the two GOP senators are both out and Democrats boycott, they will not have a majority to vote on the nomination.

To avoid this situation Lee and Tillis would have to be present to approve the nomination under Senate rules.