The 117th session of Congress will begin with both chambers meeting at noon, as required by the Constitution. 

New members of the House and Senate will be sworn in under unusual circumstances given the pandemic, with social distancing and fewer family members and supporters in attendance. 

Because control of the Senate hinges on the Georgia Senate runoffs, Republicans will begin the new Congress with control of the chamber and a 51-seat majority. The seat of Sen. David Perdue, R-Ga., will be vacant until a winner is formally certified in Tuesday's runoff election.

Sunday afternoon, the House will elect a speaker.

Nancy Pelosi is expected to win with the narrowest of margins, given Democrats’ historically slim majority, but the vote is expected to take longer than last year because of the coronavirus precautions that require lawmakers to enter the chamber in waves.

-ABC News' Mariam Khan and Benjamin Siegel

Echoing his boss, Vice President Mike Pence is apparently supportive of the GOP senators and representatives planning to object to the Electoral College's certification of results on Wednesday.

"Vice President Pence shares the concerns of millions of Americans about voter fraud and irregularities in the last election," Marc Short, Pence's chief of staff, said in a statement Saturday night. "The Vice President welcomes the efforts of members of the House and Senate to use the authority they have under the law to raise objections and bring forward evidence before the Congress and the American people on January 6th."

Sen. Josh Hawley, R-Mo., said earlier this week he would support objecting to a state's voting results, likely one of several battlegrounds, thereby giving the necessary senator and representative to force a vote over the legitimacy of that state's results. Several GOP representatives had previously said they supported the challenge, but Hawley was the first senator. Seven others, including Ted Cruz, said Saturday they also supported it.

But challenging the electors in any state is extremely unlikely to prevent Joe Biden's confirmation as the next president. For a new slate of electors to be admitted, the Senate and House have to vote in favor. With the House controlled by Democrats, that will not happen and the original electors will be used.

A spokesperson for Biden called the move a "stunt" on Saturday. Several Republicans, including Mitt Romney, Lisa Murkowski and Pat Toomey, have come out against the move by fellow senators.

Pence will preside over the session on Wednesday to certify the vote.

ABC News' Elizabeth Thomas contributed to this report.

President-elect Joe Biden and his team are not showing any concern about the breakaway group of GOP senators planning to object to the results of the Electoral College on Jan. 6.

"This stunt won't change the fact that President-elect Biden will be sworn in on January 20th, and these baseless claims have already been examined and dismissed by Trump's own Attorney General, dozens of courts, and election officials from both parties," Biden spokesperson Mike Gwin said in a statement.

The group of senators -- close allies of President Donald Trump such as Josh Hawley, Ted Cruz, James Lankford, Martha Blackburn and others -- said they will object to the slate of electors in "disputed states" unless a 10-day audit is conducted of those states' results. Yet, dozens of lawsuits about the election results have already been rejected by both conservative and liberal judges.

"Once completed, individual states would evaluate the Commission’s findings and could convene a special legislative session to certify a change in their vote, if needed," Cruz and 10 other senators and senators-elect wrote in a statement Saturday. Hawley made his intentions clear earlier this week.

That audit appears unlikely and a rejection of the slate of electors would require a majority vote in both the Senate and House. The House lies solidly in Democratic control.

ABC News' Molly Nagle contributed to this report.

Former presidential candidate Sen. Mitt Romney, R-Utah, is calling out fellow GOP senators, like Ted Cruz and Josh Hawley, who he says are undertaking an "egregious ploy" to overturn the results of the Electoral College.

Romney, himself familiar with conceding an election, joins Pennsylvania Republican Sen. Pat Toomey, who also came out against the effort Saturday.

President Donald Trump's allies, such as Hawley and Cruz, have said they plan to object to a certification of the results in a session on Jan. 6. The certification is usually a formality, but 11 senators and senators-elect plan to object this year. The move would be done in order to choose a different set of electors -- Republican electors -- even if Trump lost the vote to President-elect Joe Biden.

"The egregious ploy to reject electors may enhance the political ambition of some, but dangerously threatens our Democratic Republic," Romney said in a statement Saturday night. "The congressional power to reject electors is reserved for the most extreme and unusual circumstances. These are far from it. More Americans participated in this election than ever before, and they made their choice."

The alternate slate of electors can only be approved by a majority vote in both the Senate and House of Representatives. With the House controlled by Democrats, the move by Republicans in the Senate would largely be symbolic. Several GOP members of the House will also likely object.

Trump has made baseless claims of conspiracy and fraud daily in the two months since the election. Hawley and Cruz have made similar claims in their statements about supporting the call for different electors -- a point assailed by Romney.

"President Trump’s lawyers made their case before scores of courts; in every instance, they failed," he said in the statement. "The Justice Department found no evidence of irregularity sufficient to overturn the election. The Presidential Voter Fraud Commission disbanded without finding such evidence."

Protesters, including far-right groups like the Proud Boys, are also expected to show up in Washington on Wednesday to protest the certification of results.

"Adding to this ill-conceived endeavor by some in Congress is the President’s call for his supporters to come to the Capitol on the day when this matter is to be debated and decided," Romney said. "This has the predictable potential to lead to disruption, and worse."

"I could never have imagined seeing these things in the greatest democracy in the world," he continued. "Has ambition so eclipsed principle?"

-ABC News' Trish Turner