WASHINGTON (AP) — Republicans lack the votes to block witnesses at President Donald Trump’s impeachment trial, Senate Majority Leader Mitch McConnell conceded late Tuesday, a potentially major hurdle for Trump’s hopes to end the trial with a quick acquittal. Earlier, Trump’s lawyers concluded his defense with a plea to move on.

Even after sitting through days and late nights of argument, several Republicans apparently are ready to join Democrats in considering in-person testimony from former National Security Adviser John Bolton and perhaps others.

Trump’s lawyers made their closing case for a speedy acquittal Tuesday, but to no avail.

McConnell told colleagues in a private meeting that he did not yet have the votes to block Democrats from summoning witnesses. That outcome would prolong an election-year trial that Trump and his legal team had hoped was on track, as one lawyer said, to “end now, as soon as possible.”

McConnnell’s statement, in a closed-door meeting of senators, was an acknowledgment of the extent to which revelations from Bolton have scrambled the trial’s schedule and the desire for testimony. Bolton writes in a forthcoming book that Trump told him he wanted to withhold military aid from Ukraine until it helped with investigations into Democratic rival Joe Biden. That assertion, if true, would undercut a key defense argument and go to the heart of one major article of impeachment against the president.

Trump complained anew at a rally in Wildwood, New Jersey, focusing on Democrats rather than Republican senators.

“While we are creating jobs and killing terrorists, the congressional Democrats are obsessed with demented hoaxes, crazy witch hunts and deranged partisan crusades,” he said.

There are still several days before any potential witness vote would be taken. A decision to call more witnesses would require 51 votes to pass.

With a 53-47 majority, Republicans can only afford to lose three. If senators agree they want more witnesses they would then have to vote again on who to call.

McConnell convened the private meeting shortly after Trump’s legal team concluded their arguments in the trial, arguing forcefully against the relevance of testimony from Bolton and insisting that nothing Trump had done amounted to an impeachable offense.

While scoffing at Bolton’s book manuscript, Trump and the Republicans have strongly resisted summoning him to testify in person about what he saw and heard as Trump’s top national security adviser.

A day after the defense team largely brushed past Bolton, attorney Jay Sekulow addressed the controversy head-on by dismissing the book — said to contradict a key defense argument about Trump’s dealings with Ukraine — as “inadmissible.”

“It is not a game of leaks and unsourced manuscripts,” Sekulow said.

A night earlier Trump attorney Alan Dershowitz said that nothing in the manuscript — even if true — rises to the level of an impeachable offense. Sekulow also sought to undermine the credibility of Bolton’s book by noting that Attorney General William Barr has disputed comments attributed to him by Bolton.

Senate Republicans spent considerable time in private discussing how to deal with Bolton’s manuscript without extending the proceedings or jeopardizing the president’s expected acquittal. Those lost steam, and Democrats showed no interest.

Chuck Schumer, the Senate’s top Democrat, called a proposal for senators to be shown the manuscript in private, keeping Bolton out of public testimony, “absurd.”

“We’re not bargaining with them. We want four witnesses, and four sets of documents, then the truth will come out,” Schumer said.

Senators are being warned that if they agree to call Bolton to testify or try to access his book manuscript, the White House will block him, beginning a weeks-long court battle over executive privilege and national security.