Watch Live: Congress Begins Electoral College Tally

Updated at 10:12 a.m. ET

Under the Constitution, the final step in the 2020 presidential election is for a joint session of Congress to meet on Jan. 6 to count the Electoral College votes and officially declare a winner. Governors certified and sealed their states' results after their electors signed off on them on Dec. 14, and Joe Biden and Kamala Harris won with 306 votes to Donald Trump and Mike Pence's 232 votes.

This session is typically a ceremonial affair, but this year it's expected to highlight the bitterly divided reaction between the two parties to the 2020 election results and last for hours.

Watch the livestream beginning at 1 p.m. ET. Follow more updates here.

If any House member is joined by a senator to object to any state's electoral vote tally, they can object and force a debate and votes. More than a dozen Republican senators and a large group of House GOP lawmakers have indicated they will register challenges to multiples states' results.

Some of those members even acknowledged that they don't expect to succeed or change the outcome, but are using the process to highlight what they believe are instances of fraud. None have provided any evidence to date, and legal challenges in states mounted by the Trump campaign and its allies have consistently failed.

How the joint session will work

Vice President Pence presides over the joint session, and it is his duty under the law to announce the results. Members of the House and Senate will convene in the House chamber at 1 p.m. ET.

The certificates from each state are opened and read in alphabetical order. If any House member raises an objection, they need a senator to sign the objection in order for it to be considered. According to GOP sources familiar with the discussions about the plans, the Republican lawmakers planning to object on Wednesday are focused primarily on three states — Arizona, Georgia and Pennsylvania. They are also weighing challenges for Michigan, Nevada and Wisconsin.

Texas GOP Sen. Ted Cruz is expected to sign onto the challenge regarding Arizona's results and press for the appointment of an electoral commission that can examine any claims related to voter fraud.

Missouri Republican Sen. Josh Hawley, who was the first senator to announce he would join the House GOP effort, has indicated he is focused on Pennsylvania. Georgia Sen. Kelly Loeffler, who just lost her seat in a runoff decided overnight, announced Monday she would sign onto a challenge to her home state's results.

Process for considering and voting on an objection

If both a House member and senator register their objection in writing, the joint session is recessed, and the House and Senate meet separately to debate the issue for up to two hours. Members are allowed up to 5 minutes each to speak, and then both chambers vote. A simple majority is needed in both chambers for an objection to succeed.

With social distancing rules during the coronavirus pandemic, voting takes longer, so each objection could result in multiple hours of debate and vote timing.

House Speaker Nancy Pelosi, D-Calif., will preside over any House debate and has tapped Democratic Reps. Adam Schiff, Calif., Zoe Lofgren, Calif., Jamie Raskin, Md., and Joe Neguse, Colo., to lead any responses to GOP objections. But other Democrats from states Republicans are focused on are expected to also speak out against the effort as well.

In a letter to House Democrats on Monday evening, Pelosi called the day one "of historic significance" and says Biden and Harris won "decisively." She cautioned that members should view the session as "a solemn occasion" and "we will have a civics lesson about protecting the integrity of our democracy."

Pence, as president of the Senate, is expected to preside over the Senate debate. But Iowa GOP Sen. Chuck Grassley, who is president pro tem, is prepared to also be available if Pence is not available for any portion of the debate. The president falsely claimed the vice president could alter the results, but neither the Constitution or any federal law allows for that.

An administration official who was not authorized to speak on the record told NPR on Tuesday, "The VP intends to follow the law and uphold the Constitution tomorrow." This official noted that Pence, who is a lawyer by training, has prepared for the joint session by meeting with the Senate parliamentarian, reading legal opinions and studying the Constitution.

After the New York Times reported Tuesday that Pence told the president at a lunch at the White House that he does not have the ability to block the certification for Biden, Trump released a statement late in the evening calling that report "fake news."

The statement from the president maintains: "The Vice President and I are in total agreement that the Vice President has the power to act" and the vice president has "several options under the U.S. Constitution." The Times stands by its reporting.

After each chamber votes — and no challenge is expected to garner enough to succeed — the members of House and Senate return to the joint session and move onto the next state. After they have processed all the results, Pence reads the final tally and announces the election results for president and vice president.

Leaders have warned members the process is likely to last several hours and could involve late-night votes. Democrats hold the majority in the House and roughly two dozen Republicans in the Senate, including Senate Majority Leader Mitch McConnell, R-Ky., have indicated they will join Democrats to certify Biden as the winner, so the outcome is not in doubt.

Thousands of pro-Trump protesters are expected to descend on Washington to voice support for the GOP objections. D.C. Mayor Muriel Bowser has advised residents to stay away from downtown and local law enforcement is prepared to respond to any possible violent demonstrations.

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