Senate Majority Leader Chuck Schumer will not allow Sen.-elect Dave McCormick (R-Pa.) to participate in Senate orientation this week because he doesn’t consider the race to be resolved yet.

Though the Associated Press projected Thursday that McCormick defeated Democrat incumbent Bob Casey in Pennsylvania’s Senate race, Casey has yet to concede, claiming that there are still thousands of ballots left to be counted.

“With over 100,000 ballots left to be counted in Pennsylvania, the race has not been decided. As is custom, we will invite the winner once the votes are counted,” a spokesperson for Schumer wrote in a statement. As of Sunday at 4:30 p.m., McCormick was ahead by approximately 39,000 votes.

“Schumer is not allowing @DaveMcCormickPAto participate in Senate orientation this week because Casey refuses to concede the race. What happened to all the demands that our leaders accept the outcome of the elections?” Sen. Marco Rubio (R-Fla.) said in a social media post Sunday.

Rep. Ruben Gallego (D-Ariz.) has also not been invited to orientation yet as his race against Republican Kari Lake has yet to be called. Gallego is ahead by approximately 48,000 votes. (The Associated Press has not called that race; the New York Times has not called either the Pennsylvania or Arizona race.)

On Wednesday, Republican senators will vote for the next majority leader, who will begin serving in January. The three front-runners are Florida Sen. Rick Scott, South Dakota Sen. John Thune and Texas Sen. John Cornyn.

When asked on Fox News’ “Sunday Morning Futures” who he would support for majority leader, McCormick told host Maria Bartiromo, “I’m still just now spending time with each of the candidates, and I will have an opportunity to vote this week.”

He added that he would not speak about the pros and cons of each candidate, but emphasized the need to be “in step with President Trump.”

In response to Schumer’s decision to prevent McCormick from participating, Republican politicians have been speaking out, including the majority leader-hopefuls.

“The idea that Schumer would not allow him to participate in Senate orientation is beyond unacceptable,” Thune wrote in a social media post Sunday. “The voters of Pennsylvania have spoken. Looking forward to having Dave’s strong voice in the Senate Republican Conference.”

Scott called the move “disgusting” and said, “They did the same thing to me after I beat a Democrat in 2018. We have to fight this!”

Cornyn called on Casey to concede and reposted a statement by Sen. Mike Lee (R-Utah), which said: “I can’t think of another time when a senator-elect has been excluded from the Senate’s week-long orientation for new senators.”

McCormick argued that there’s no way Casey can gain enough votes at this point to defeat him.

“Mathematically, there’s no path for Senator Casey to win,” McCormick said on Fox. “Currently, I’m up by something like 40,000 votes, which is a very significant margin. And ultimately, Senator Casey’s going to have to decide when he’s willing to acknowledge that.”