Then, senators are expected to work through a number of housekeeping issues — including swearing in Chief Justice John Roberts and passing a rules package — before the trial really begins. Senate Republicans expect the trial to effectively begin on Tuesday following the Martin Luther King Jr., holiday beginning with the organizing resolution.

McConnell laid out how that will go: By the end of this week senators should be sworn in as jurors. Then next week they will hear opening arguments from Pelosi's managers and the president's defense. Senators will submit written questions to Roberts for the question and answer period. They then will tackle the question of witnesses and other new evidence.

Pelosi on Tuesday also encouraged House Democrats to push back on Trump's recent call for an outright dismissal of the trial, something several Senate Republicans also said they would be against.

"Dismissal is a cover-up," Pelosi told the caucus, according to Democrats present.

In an interview, Sen. Lisa Murkowski (R-Alaska) said she would oppose dismissal, joining Sens. Mitt Romney (R-Utah) and Susan Collins (R-Maine). And McConnell made clear that he didn't think much of the idea either.

“There’s little to no sentiment in the Republican Conference for a motion to dismiss. Our members feel they have an obligation to listen to the arguments," McConnell said.

Pelosi faced criticism from Republicans and even some Senate Democrats for withholding the articles, first demanding that McConnell compromise on the rules of the trial.

Pelosi and Senate Minority Leader Chuck Schumer (D-N.Y.) called on McConnell to agree ahead of time to call witnesses and request documents related to the Ukraine investigation that had been blocked by the White House for months.

McConnell rejected their requests and refused to relent, announcing last week that he had enough Republican support to push through a trial framework that would allow senators to force votes on witness and document requests later in the trial but not ahead of time.

McConnell taunted Pelosi last week, arguing she had no leverage and should send the articles over so the chamber can begin its trial. But Pelosi and her allies maintain the strategy was a success, pointing to the evidence that has come out in the weeks since the House impeached Trump.

"When I heard Leader McConnell three weeks ago and asked him for witnesses and documents, he didn’t pay much attention," Schumer said. "Soon we're going to have an opportunity to see where my Republican colleagues really stand on witnesses testifying and documents."

Senate Democrats are expected to force votes on witnesses during the trial, including former national security adviser John Bolton, who has said he would testify if subpoenaed.

Despite being unified on how to start the trial, Senate Republicans are divided over whether to call witnesses later. Some moderate Republicans, including Collins, Murkowski and Romney, have said they’re open to hearing from witnesses during the trial. But so are Trump hard-liners like Sen. Rand Paul (R-Ky.), who can force votes on hearing from Joe Biden and his son, among others.

“We’ll be dealing with the witness issue at the appropriate time into the trial. And I think it’s certainly appropriate to point out that both sides would want to call witnesses if they wanted to hear from them. So if you get to that issue I can’t imagine that only the witnesses our Democratic colleagues want to call will be called," McConnell said.



