President-elect Donald Trump called on Republican senators again Wednesday to halt Democrats from confirming more of President Biden’s judicial nominees before he takes office on Jan. 20.

Senate Democrats have been moving swiftly to confirm pending vacancies before they lose control of the upper chamber on Jan. 3, following the new GOP majority’s victories earlier this month. Senate Republicans will have a 53-47 majority in the new Congress.

“The Democrats are trying to stack the Courts with Radical Left Judges on their way out the door. Republican Senators need to Show Up and Hold the Line — No more Judges confirmed before Inauguration Day!” Mr. Trump wrote on X.

Sen. Thom Tillis, North Carolina Republican, said he is “very angry” about his GOP colleagues who have missed votes this week as Democrats attempt to confirm more Biden-nominated judges.

He said if Republicans had full attendance on Monday evening when one Democrat was absent, they could have defeated a number of procedural motions Democrats made to advance more of Mr. Biden’s nominees. 

“We could have stopped those 18 votes after the first vote, if we had shown up that day — not every day, but that day,” Mr. Tillis said. 

Five Republican senators were absent on Monday, including Sens. J.D. Vance of Ohio, the vice president-elect, and Mike Braun, the governor-elect of Indiana. 

Senate Democrats, with their current 51-49 majority, can advance any nominees on which their party is united, but only if they have more senators in attendance and voting than Republicans voting in opposition. 

Mr. Tillis said if Republicans don’t show up for votes, Senate Majority Leader Charles E. Schumer will take advantage of those absences, particularly in cases where Democrats may not be united on nominees. 

“I got a Fourth Circuit nominee that if my colleagues show up on my side, I’ve secured Democrat votes to defeat,” Mr. Tillis said. “That is very personal to me. For one of the most liberal circuits in the nation, and we can prevent that nomination. It only happens if Chuck Schumer takes advantage of an absenteeism, which I suspect he may do.”

Mr. Schumer said of the GOP, “They can try dilatory tactics, but we’re going to persist.”

Demand Justice, a liberal advocacy group, has called on Democrats to push through judicial nominees that haven’t yet been seated to the bench. 

There are currently 17 judicial nominees awaiting Senate confirmation votes for Article III appointments, and 45 court vacancies overall. 

Mr. Biden has thus far won the confirmations of one Supreme Court justice, Ketanji Brown Jackson; 45 circuit court and 171 district court judges during his four years in office.

By comparison, Mr. Trump appointed three Supreme Court justices, 54 circuit court judges and 174 district court jurists during his first administration.

• Lindsey McPherson can be reached at [email protected].

• Alex Swoyer can be reached at [email protected].