Senate jurors peppered President Donald Trump’s defenders and accusers with final questions at his impeachment trial Thursday ahead of a crucial vote on calling witnesses, the focus shifting from details of the charges to whether it was time to simply acquit and conclude the trial.

The vote on witnesses, expected Friday, could lead to an abrupt end of the trial with the expected acquittal. Or, less likely, it could bring weeks more of argument a s Democrats press to hear testimony f rom former national security adviser John Bolton and others.

Thursday’s testimony included soaring pleas to the senators who will decide Trump’s fate, to either stop a president who Democrats said tried to cheat in the 2016 election and will again, or to shut down impeachment proceedings that Republicans insisted were never more than a partisan attack.

“Let’s give the country a trial they can be proud of,” said Rep. Adam Schiff, the lead prosecutor for House Democrats. Americans, he said, know what it takes for a fair trial and won’t stand for anything less.

Trump attorney Eric Herschmann countered that Democrats are only prosecuting the president because they can’t beat him in the 2020 election.

“We trust the American people to decide who should be our president,” Herschmann said. “Enough is Enough. Stop all of this.”

Watch day 10 of the trial here.

Late Thursday morning, ABC News reported Senate Majority Leader Mitch McConnell believes he has enough votes to block Democrat-led efforts to call witnesses.

If enough Republicans cross the aisle and vote with Democrats, Trump’s impeachment trial will have no immediate end in sight. But if party caucuses hold along a GOP-led 53-47 line, the trial could end as soon as Friday or Saturday.

If witnesses are called, as Democrats have been demanding since the articles were passed by the House, one name at the top of everyone’s list is former National Security Adviser John Bolton, whose forthcoming book has changed the entire impeachment landscape.

Democrats argued Bolton’s forthcoming book cannot be ignored. It contends he personally heard Trump say he wanted military aid withheld from Ukraine until it agreed to investigate Joe Biden and his son, Hunter Biden — the abuse of power charge that is the first article of impeachment.

On Wednesday, Trump’s defense told senators a trade of U.S. military aid for political favors — even if proven — could not be grounds for his impeachment.

Several GOP senators are reportedly undecided on whether to allow witness testimony in President Trump's impeachment trial. They are: Mitt Romney, Utah Susan Collins, Maine Lisa Murkowski, Alaska Pat Toomey, Pennsylvania Rob Portman, Ohio Jerry Moran, Kansas Cory Gardner, Colorado Lamar Alexander, Tennessee Prosecutors and defenders in Trump's trial have finished their opening arguments. Senators will now begin deliberations, submit written questions, and decide on President Trump's fate.

Trump’s defenders relied on retired professor Alan Dershowitz, a member of their team, who told senators that every politician conflates his own interest with the public interest. “It cannot be impeachable,” he declared Wednesday.

Democrats pressed hard to force the Senate to call more witnesses to testify, but Republicans appeared intently focused on bringing the impeachment trial to a vote of acquittal, possibly in a matter of days.

Bolton’s revelations were countered by the president’s lawyers, who used Wednesday’s session to warn off prolonging the proceeding, insisting senators have heard enough.

»MORE: Trump trial gets more pointed after first day of Q&As

Dozens of questions were asked and answered Wednesday in five-minute clips, with senators under orders to sit silently without comment, submitting their questions in writing. They finished shortly past 11 p.m.

Here are the key figures in President Donald Trump's impeachment trial. House Speaker Nancy Pelosi. She led the impeachment effort. Chief Justice John Roberts. He will preside over the trial. The Senate's political leaders - Majority Leader Mitch McConnell and Minority Leader Chuck Schumer. The president's legal defense team - White House counsel Pat Cipollone, Trump personal lawyer Jay Sekulow, Kenneth W. Starr, Alan Dershowitz, along with Robert Ray and Jane Raskin. House Democratic impeachment managers

Democratic leader Chuck Schumer asked whether the Senate could really render a fair verdict without hearing from Bolton or acting White House chief of staff Mick Mulvaney, both potential eyewitnesses to Trump’s actions.

“Don’t wait for the book. Don’t wait ’til March 17, when it is in black and white to find out the answer to your question,” Schiff told the Senate.

House Speaker Nancy Pelosi has named seven impeachment managers for President Donald Trump's upcoming Senate trial: U.S. Rep. Adam Schiff of California, chair of the House Intelligence Committee, and lead manager U.S. Rep. Jerrold Nadler of New York, chair of the House Judiciary Committee U.S. Rep. Zoe Lofgren of California U.S. Rep. Hakeem Jeffries of New York U.S. Rep. Val Demings of Florida U.S. Rep. Jason Crow of Colorado U.S. Rep. Sylvia Garcia of Texas Senate Majority Leader Mitch McConnell expects

That publication date is now in doubt. The White House on Wednesday released a letter to Bolton’s attorney objecting to “significant amounts of classified information” in the manuscript, including at the top secret level. Bolton and his attorney have insisted the book does not contain any classified information.

»MORE: Democrats want to ‘overturn’ last election, Trump’s lawyers argue

The White House action could delay the book’s publication if Bolton, who resigned last September — Trump says he was fired — is forced to revise his draft.

GOP senators are straining to balance the new revelations with pressure for quick acquittal. They have been sternly warned by party leaders that calling Bolton as a witness could entangle the trial in lengthy legal battles and delay Trump’s expected acquittal.

Donald Trump has become the third American president to be impeached. Trump has been charged with abuse of power and obstruction of Congress. Led by Democrats, the U.S. House of Representatives passed the articles of impeachment on Dec. 18, 2019. Trump will face trial in the GOP-controlled Senate in 2020, a presidential election year. Presidents Andrew Johnson and Bill Clinton were also impeached. Neither was removed from office.

White House lawyers made exactly that point. Attorney Pat Philbin said in response to the Democrats’ first question, “This institution will effectively be paralyzed for months.”

»MORE: Democrats wrap up final day of opening arguments

Senate Majority Leader Mitch McConnell huddled privately with senators for a third consecutive day, acknowledging he didn’t yet have the votes to brush back Democratic demands for witnesses now that revelations from Bolton have roiled the trial. But Republicans said they were making progress.

Republican ideas for dealing with Bolton and his book were fizzling almost as soon as they arose — among them, “swapping” witnesses with Democrats or issuing a subpoena for Bolton’s manuscript.

Most Republican senators don’t want to extend the trial by calling Bolton, and most Democrats would rather avoid dragging the Bidens further into the impeachment proceedings. The Bidens were a focus of defense arguments.

How is your senator trending on impeachment?