Republicans are already threatening to block Kamala Harris from nominating justices to the U.S. Supreme Court.

Two of the leading candidates to replace Senate minority leader Mitch McConnell refused to commit to allowing a confirmation vote for a Harris nominee if she’s elected president and Republicans retake the Senate majority, reported CNN.

“It depends,” said Sen. John Cornyn (R-TX). “Obviously, they would have to go through the committee process, and so it would depend on that, and then I think it would also depend on who the president nominates.”

“If I’m in a position to make the decision, I’m not going to schedule a vote on some wild-eyed radical nominee, which I know she would love to nominate,” Cornyn added. “But that would be my intention.”

Senate GOP whip John Thune (R-SD), another leading candidate to replace McConnell as leader, echoed Cornyn’s threats.

“We’ll cross the bridge when we come to it,” Thune said. “But, you know, it probably depends on who it is and that’s the advantage of having a Republican Senate.”

McConnell himself blocked former president Barack Obama from getting his nominee confirmed to replace the late Antonin Scalia in 2016, and that break with tradition looks to continue if Republicans retake the majority, as they’re heavily favored to win in November.

“We would be the loyal opposition,” Cornyn said.