Trump adviser Jason Miller has walked back and forth on Capitol Hill with a stack of papers he says is a witness list and has 301 names -- "SO FAR," the top page reads.

He told ABC News he’s not ready to share the whole thing yet because it’s a work in progress, but it signals Trump's team will match Democrats' call to have witnesses by potentially inundating the trial with them.

Miller's pacing comes as Republican Sen. Lindsey Graham has doubled down on his call for multiple witnesses -- if any are ultimately called with the resolution.

"It is my firm belief that the House Managers are trying to investigate the case AFTER it was brought to the Senate. It is better for the country to go to a final vote," Graham tweeted. "However, if the body wants witnesses, I am going to insist we have multiple witnesses."

Graham said the Senate could start with House Speaker Nancy Pelosi -- a sentiment floated by Trump defense attorney Michael van der Veen on the floor Saturday when he called for the trial to end "today."

The scramble for party leaders to work on a trial resolution for witnesses comes after the unexpected vote and call from House managers to subpoena Republican Rep. Jaime Herrera Beutler, who has said she has information on an intense call House Minority Leader Kevin McCarthy had with Trump during the Capitol attack, in which Trump sided with the mob while violence was underway.

-ABC News' Katherine Faulders and Allison Pecorin

After the Senate moved in a 55-45 vote to consider a resolution to call specific witnesses, Senate leaders are now meeting to draft that resolution.

According to sources, it should contain specific information on how the trial will move forward.

The resolution will be amendable, which means Republicans could offer endless amendments. Each amendment would get two hours of debate before a vote. Many want to avoid that situation, according to sources.

Sen. Chris Murphy, D-Conn., told ABC News the House managers could still decide to call no witnesses. In the end, the Senate will need to vote again on the resolution, which requires a simple majority vote to pass.

Lawmakers have begun to go back to their office building, so it appears the trial is in a holding pattern for some time.

-ABC News' Trish Turner

The Senate has called a recess until 12:30 p.m. as Senate leaders draft a resolution to call for witnesses in Trump's trial, following a 55-45 vote.

According to sources, the resolution -- which the Senate will need to vote on -- should contain specific information on how the trial will move forward.

Senators on both sides of the aisle seemed surprised by House impeachment managers' move to call for witnesses Saturday, according to pool reporters inside the chamber.

Sen. Ron Johnson, R-Wis., turned to Sen. Mitt Romney, R-Utah., at one point and was visibly upset with him, even pointing at him once. The two went back and forth with Sen. Dan Sullivan, R-Alaska, in the middle of them.

Johnson said, "We should've just ended this, that's all I'm saying," and told Romney, "Blame you."

Romney was the only Republican to vote to convict Trump at his last impeachment trial.

When lead House impeachment manager Rep. Jamie Raskin, D-Md., raised bringing in Rep. Jamie Hererra Beutler, D-Wash., as a witness, Sen. Lindsey Graham, R-S.C., shook his head no and put his head down on his hand on his forehead.

Graham later joined four Republicans --Sens. Mitt Romney, Susan Collins, Lisa Murkowski and Ben Sasse -- in voting to hear witnesses after threatening to delay the trial with witnesses of his own.

After the Senate decided it will not call any witnesses, lead House manager Rep. Jamie Raskin, D-Md., was the first to speak during closing arguments. He reiterated the prosecution's case, calling for the conviction of Trump.

"It was suggested by defense counsel that Donald Trump's conduct during the attack, as described in Congresswoman Beutler's statement, is somehow not part of the Constitutional offense for which former President Trump has been charged," Raskin began. "I want to reject that falsehood and that fallacy immediately. After he knew that violence was underway at the Capitol, President Trump took actions that further incited the insurgents to be more inflamed and to take even more extreme, selective, and focused action against Vice President Mike Pence."

Raskin went on to use his time to describe Trump's months-long campaign to discredit the 2020 election results by spreading misinformation, which he argued laid the groundwork for deadly events of Jan. 6. He went on to claim that the former president assembled the mob, incited it and then sent it off to the Capitol during his speech. At every point, Trump sided with the insurrectionists rather than the Congress, Raskin said.

Once when the violence began, Raskin declared that Trump ignored the violence and further incited it by aiming the attacks on his own vice president.

"There has never been a greater betrayal by the president of the United States of his office, and of his oath to the Constitution."

Raskin then took a moment to suggest the GOP used "cancel culture" against one of its leaders, Rep. Liz Cheney, R-Wyo., who voted to impeach Trump in the House.

"Liz Cheney is a hero for standing up for the truth, and resisting this retaliatory cancel culture that she was subjected to."

Raskin emphasized his gratitude toward the Capitol Police, and finished his argument by saying convicting Trump is a vote for the "security of our democracy."

"They attacked this building, they disrupted the peaceful transfer of power, they injured and killed people, convinced that they were acting on his instructions, and with his approval, and protection," Raskin finished. "And while that happened, he further incited them, while failing to defend us. If that's not ground for conviction, if that's not a high crime and misdemeanor against the republic in the United States of America then nothing is. President Trump must be convicted for the safety and security of our democracy and our people."