Georgia election official Gabriel Sterling, a Republican, at a press conference on what he called "anti-disinformation Monday," ran through major voter conspiracies pushed by Trump, his allies and far-right media outlets and debunked them one-by-one in an effort to restore faith in Georgia's election system.

"The reason I'm having to stand here today is because there are people in positions of authority and respect who have said their vote didn't count and it's not true," Sterling said, stressing to Georgians that their votes count ahead of critical runoffs in the state which will determine the balance of power in the U.S. Senate.

"It's Whac-A-Mole again. It is Groundhog Day again. I'm going to talk about the things I've talked about repeatedly for two months, but I'm going to do it for one last time," Sterling said, adding he "screamed" at the radio upon hearing audio of the phone call between Trump and Secretary of State Brad Raffensperger because theories Trump questioned have already been "thoroughly debunked."

For example, Sterling, responding to those who claim there were roughly 2,500 people who voted without being registered, said, "Let's just be clear about this: you can't do it!" He said, "So that number is zero," going on to debunk other theories.

Asked if he believes, as some have said, that Trump's phone call was an attack on democracy, Sterling said he'd leave others to make that decision before adding he felt it was "out of place."

"I found it to be something that was not normal -- out of place -- and nobody I know who would be president would do something like that to a secretary of state," Sterling said.

Asked about Raffenperger's desire to have the phone call recorded and whether he was concerned about anything improper being said or needing to release it later, Sterling said it was recorded "out of an abundance of caution"

"I think given the environment we're in right now, the political situation that we're in, the history of the president, knowing that he sometimes doesn't necessarily characterize things as they might have actually occurred, it was out of abundance of caution," Sterling said.

"I'm sure the president's side may have recorded it, too. They may have been the ones who leaked part of that, too," he added.

NAACP President Derrick Johnson is slamming Trump's phone call with Georgia Secretary of State Brad Raffensperger and, in a new statement Monday, calls on the Fulton County District Attorney to investigate any state law violations committed by Trump after he "pressured" Raffensperger to recalculate votes in his favor.

"This is a racist attack on Black voters. President Trump's desperate and futile attempts to invalidate and falsify votes cast by Georgia voters add to a growing list of criminal acts that must be addressed," Johnson said in a statement.

Trump, in an hour-long phone call with Raffensperger on Saturday, falsely claimed it was "not possible" for him to have lost in The Peach State, and asked the secretary to "find" the exact number of votes he would need -- just one vote over the margin that he trailed Biden by -- so he could be declared the winner of an election that three separate counts confirmed he lost.

Fulton County District Attorney Fani Willis, in statement earlier Monday, did not rule out the possibility of filing state charges against Trump or his aides involved in the call, saying that it is her understanding Raffensperger's Elections Division has been requested to investigate the call and that, upon the conclusion of their investigation, the matter can be referred to both her office and the state's attorney general Chris Carr for potential charges.

-ABC News' Beatrice Peterson and Alexander Mallin

Biden is headed to Georgia on Monday afternoon where the Senate's balance of power -- and the president-elect's subsequent hopes to pass the big ticket legislation he campaigned on -- hangs on a pair of Senate runoff elections.

The Georgia races have drawn national attention with both parties mobilizing their supporters ahead of the Jan. 5 election date. While Biden stumps in Atlanta Monday for Democratic contenders Rev. Raphael Warnock and Jon Ossoff, Trump headlines an evening rally in Dalton for sitting GOP Sens. Kelly Loeffler and David Perdue.

If Democrats win both races, the partisan make-up of the Senate will be 50-50, including the independents who caucus with Democrats, and Vice President Kamala Harris would serve as the tie-breaking vote in the Congress' upper chamber.

More than 3 million Georgians voted early in the races -- a record for statewide runoff elections in the Peach State.

-ABC News' Adia Robinson

Vice President Mike Pence, stumping for GOP Georgia senators on the eve of runoff elections there, vowed Republicans will have "our day in Congress" to contest the Electoral College results while urging supporters to put their immediate focus on defending the party's majority in the Senate.

"I know we’ve all got our doubts about the last election," Pence told hundreds of mostly maskless supporters inside a church in Milner, Georgia. "And I want to assure you I share the concerns of millions of Americans about voting irregularities. And I promise you, come this Wednesday, we’ll have our day in Congress. We’ll hear the objections. We’ll hear the evidence. But tomorrow it’s Georgia’s day."

Recent polls show tight races between sitting GOP Sens. David Perdue and Kelly Loeffler and Democratic contenders Jon Ossoff and Rev. Raphael Warnock -- forcing star power to the Peach State on the eve of the election including visits from Trump and Biden later on Monday.

-ABC News' Justin Gomez

Three days after Capitol Police Officer Brian Sicknick died defending the Capitol against insurrectionists the White House lowered the U.S. flag to half-staff.

The decision to lower the flags came hours after Capitol Police also announced the off-duty death of Officer Howard Liebengood. The circumstances of his death have not been made public.

The U.S. attorney's office in Washington opened a federal murder investigation into the death of Sicknick, who died Thursday night after suffering injuries in the violent siege on Capitol Hill, three law enforcement sources confirmed to ABC News.

The investigation is being conducted jointly between the FBI and the D.C. Metropolitan Police Department, with cooperation from U.S. Capitol Police.
Acting Attorney General Jeffrey Rosen said in a statement that the Department of Justice "will spare no resources in investigating and holding accountable those responsible."

-ABC News' Elizabeth Thomas