Election 2020 updates: Biden warns of 'dark winter,' pushes masks in pandemic plan

Georgia Secretary of State Brad Raffensperger posted on Facebook that Fulton County, the state's largest, "discovered an issue involving reporting from their work on Friday."

The updated vote from Fulton County on Friday night took Biden from an approximate 4,000-vote lead to an approximate 7,000-vote lead. Roughly 5,000 votes were uploaded from the county. The statement from Raffensperger did not specify what the issue was. 

"Officials are at State Farm Arena to rescan their work from Friday. The Secretary of State has a monitor onsite, has sent additional investigators, and dispatched the Deputy Secretary of State as well to oversee the process to make sure to thoroughly secure the vote and protect all legal votes. Observers from both political parties are there as well," Raffensperger said in the statement. 

ABC News obtained a statement from Fulton County that said after Director of Elections & Registration Rick Barron asked staff to review Friday night's reporting to ensure all provisional ballots were reflected in the reported results, Barron learned that "some ballots were not captured" and "a smaller number (sic) were not scanned."

"Out of an abundance of caution, all provisional, military and UOCAVA allots scanned on Friday, November 6 will be rescanned tonight. The upload made last night will be pulled and replaced with tonight’s rescanned file," the statement continued.- Quinn Scanlan

As Joe Biden takes the stage in Delaware Saturday night to deliver a victory speech, the Trump campaign is grappling with the reality of a loss.

"It's a horrible feeling," one Trump campaign aide told ABC News after the major networks called the race for Biden. Some staffers said they'd come to grips with losing in recent days, others said it didn't feel real until Fox News made the final call on Saturday, according to sources.

Though the Trump team has filed lawsuits in several states, sources familiar with the actions stress to ABC News that there has been internal bickering over the suits with some members of the president's legal team feeling they are "pointless" and "meritless."

With new numbers in from Apache and Coconino counties, Biden’s lead has widened slightly in Arizona. 

Biden's vote lead has jumped back up to 21,188 votes. He still leads 49.5% to Trump's 48.9%. 

The Arizona Secretary of State's office has not provided specific guidance on timing of the estimated 120,000 outstanding votes. 

It has, however, updated its website showing a more detailed look at which votes are outstanding. 

There are an estimated 12,199 early ballots waiting for signature verification, an estimated 45,507 provisional ballots left to process and an estimated 61,472 ballots waiting for tabulation, the office said. 

- ABC News’ Meg Cunningham

In an update to the Cybersecurity and Infrastructure Security Agency Rumor Control page, the agency assured Americans that there are robust safeguards in place to ensure accuracy of election results. 

“The systems and processes used by election officials to tabulate votes and certify official results are protected by various safeguards that help ensure the accuracy of election results,” the agency, a branch of the Department of Homeland Security, said.

It continued: “These safeguards include measures that help ensure tabulation systems function as intended, protect against malicious software, and enable the identification and correction of any irregularities.”