Sen. Sherrod Brown, D-Ohio, called on the U.S. Senate to expel Sens. Ted Cruz, R-Texas, and Josh Hawley, R-Mo., if the senators refuse to resign in the aftermath of this week's siege on the Capitol.

"Both @HawleyMO and @SenTedCruz have betrayed their oaths of office and abetted a violent insurrection on our democracy," Brown wrote on Twitter. "I am calling for their immediate resignations. If they do not resign, the Senate must expel them."

Both Republican senators have faced bipartisan condemnation for their roles in opposing the ratification of Electoral College votes.

-ABC News' Trish Turner

Sen. Pat Toomey, R-Pa., said Saturday that he believes the president "committed impeachable offenses" after the violent siege on the Capitol this week by a pro-Trump mob.

"I have to say I do think the president’s behavior this week does disqualify him from serving," Toomey said on Fox News.

"I don't know what they are going to send over," he said of the House effort to draw up an article of impeachment. "And one of the things I am concerned about frankly, is whether the House would completely politicize something. I do think the president committed impeachable offenses, but I don't know what's going to land on the Senate floor, if anything," he added.

The Republican senator voted against the objections to counting the electoral votes from Arizona and Pennsylvania this week.

While the senator did not explicitly call for Trump's removal from office, Toomey's comments come amid increased calls by Republicans to hold the president accountable for Wednesday's riot. Sen. Lisa Murkowski, R-Alaska, and Rep. Adam Kinzinger, R-Ill., have both called for Trump to vacate the presidency.

West Virginia Delegate Derrick Evans resigned Saturday after being charged for his involvement in the violent siege of the U.S. Capitol this week.

“The past few days have certainly been a difficult time for my family, colleagues and myself, so I feel it’s best at this point to resign my seat in the House and focus on my personal situation and those I love,” Evans said in a statement.

The West Virginia Republican was taken into custody Friday and charged with one count of knowingly entering or remaining in any restricted building or grounds without lawful authority and one count of violent entry and disorderly conduct on Capitol Grounds," according to the criminal complaint.

Evans had recorded himself and other supporters of Trump rushing into the Capitol after breaching the security barrier Wednesday. He has since deleted the video from his social media accounts.

-ABC News' Lucien Bruggeman and Joshua Hoyos

In December, while a signature match audit was ongoing in one Georgia county, President Donald Trump phoned a chief investigator in Secretary of State Brad Raffensperger's office asking the official to "find the fraud" and telling this person they would be a "national hero" for it, an individual familiar with the matter confirmed to ABC News.

The Washington Post was first to report on the lengthy phone call, which occurred before Trump's stunning, hourlong phone conversation with Raffensperger in which the president ranted about baseless allegations of election fraud and pressured Georgia's top elections official to "find" enough votes to deliver him a win in the Peach State.

That call, which took place on Jan. 2, is cited in the draft article of impeachment against the president that Democrats could introduce as early as Monday.

Deputy Secretary of State Jordan Fuchs confirmed the call between Trump and the chief investigator took place without offering details, saying only: "The secretary and the secretary of state's office can confirm that the call did happen."

The White House declined to comment.

-ABC News' Quinn Scanlan

At District of Columbia Mayor Muriel Bowser's request, Army Secretary Ryan McCarthy has activated about 340 unarmed D.C. National Guardsmen to assist local law enforcement with the demonstrations taking place on Wednesday pegged to the Electoral College certification.

"We think it's helpful to have our D.C. Guardsmen, who are our Guard, that I have requested from the Secretary of the Army to assist MPD [Metropolitan Police Department] with traffic management," Bowser said Monday. "It absolutely frees up more officers."

The D.C. Guard is unique in that any call-ups have to be made by the Army secretary and not the jurisdiction’s top elected official -- as is the case with state governors. Additionally, more focus has been given to the call-ups since the controversial presence of D.C. Guardsmen and the use of D.C. Guard helicopters during the Black Lives Matter demonstrations last summer.

"They will be deployed to assist us with crowd management, as well as traffic control in our nation's capital that will allow for the police officers to focus on anyone who's intent on instigating agitating or participating in violence in our city," said D.C. Police Chief Robert Contee. He also labeled any possibility of violence surrounding the protests as "unacceptable" and repeated that carrying firearms is not allowed under D.C. law.

A senior defense official said Bowser put in the request for Guardsmen on Dec. 31 and that it was approved Monday morning. Beginning Tuesday through Thursday, the 340 personnel will help man 30 traffic control checkpoints around the northern side of the downtown area close to the National Mall.

"No one's going to be armed or body armor or anything like that," said the official. "What they need is traffic control."

-ABC News' Luis Martinez and Quinn Owen