Votes are still being counted across the state, though many from counties where Biden was in the lead.
Biden inched past the incumbent in the tally Friday and by Sunday was leading by 9,160 votes of nearly 5 million ballots cast. Under Georgia state law, a candidate can request a recount if the margin is within 0.5 percentage points.
Electoral research conducted by the AP found there have been at least 31 statewide recounts since 2000. Three of those changed the outcome of the election. The initial margins in those races were 137 votes, 215 votes and 261 votes.
Among all 31 recounts, the largest shift in results was 0.1%, in the 2006 race for Vermont's Auditor of Accounts. This was a low-turnout election in which the initial results had one candidate winning by 137 votes. The candidate eventually lost by 102 votes, for a swing of 239 votes.
The average shift in the margin between the top two candidates was 0.019 percentage points.
On Saturday, Georgia Secretary of State Brad Raffensperger announced a potential vote count issue in Fulton County, one of the most-watched counties in the state.
"Fulton County has discovered an issue involving reporting from their work on Friday. 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."
The updated vote from Fulton Friday night took Biden from an approx. 4,000 vote lead to approx. 7,000 vote lead. Roughly 5,000 votes were uploaded from the county.
GA presidential race
Democrat Joe Biden is now leading President Donald Trump in the battleground state of Georgia with a margin narrow enough to trigger a possible recount when results are final.
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*Counties are colored red or blue when the % expected vote reporting reaches a set threshold. This threshold varies by state and is based on patterns of past vote reporting and expectations about how the vote will report this year.
Biden overtook Trump's lead Friday, a must-win state for the president with 16 electoral votes that has long been a Republican stronghold.
As Saturday at 6:30 a.m. ET, the former vice president now has a 7,248-vote advantage over Trump. Biden has 2,461,455 votes, while the president maintains 2,454,207.
SEE ALSO: All eyes on Stacey Abrams as Joe Biden passes Donald Trump in traditionally ruby-red Georgia
All eyes on Stacey Abrams as Joe Biden passes Donald Trump in traditionally ruby-red Georgia
Votes are still being counted across the state, though many from counties where Biden was in the lead.
Secretary of State Brad Raffensperger said Friday morning that an estimated 5,000 outstanding ballots are left to be reported -- though an ABC News analysis indicates that up to 15,000 ballots may be left outstanding.
That includes provisional ballots and absentee ballots that have to be "cured" before being scanned. Ballots cast before Election Day by military voters and citizens living overseas also needed to be received by 5 p.m. Friday. Not all of these votes will be counted.
MORE: What's a 'cured ballot' in the 2020 presidential election?
Raffensperger alluded to a recount in a Friday morning press conference, but Georgia has no automatic or mandatory recount and can only do so if the margin between the two candidates is less than 0.5% of the total votes. According to Gabriel Sterling in the secretary of state's office, recounts cannot be requested until after results are certified.
Trump's campaign is raising its campaign fund off of an "upcoming" recount in Georgia.
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"Georgia is headed for a recount, where we are confident we will find ballots improperly harvested, and where President Trump will ultimately prevail," the Trump campaign wrote in an email sent to supporters.
Electoral research conducted by the AP found there have been at least 31 statewide recounts since 2000. Three of those changed the outcome of the election. The initial margins in those races were 137 votes, 215 votes and 261 votes.
MORE: How vote recounts happen in battleground states
Advocates for both presidential candidates raced to find every person in Georgia who submitted a flawed ballot before time ran out Friday to fix the paperwork in a race that could be decided by the narrowest of margins.
Hours before the 5 p.m. deadline, Christin Clatterbuck and Sarah Meng joined about 20 other volunteers who planned to visit addresses in suburban Atlanta's Gwinnett County in search of voters whose ballots were initially rejected but could be fixed with a signature or an ID.
Cam Ashling, a Democratic activist who organized the small effort, gave instructions and a pep talk. "Never has it ever been more true than now that every vote counts," she shouted beside a pickup truck with a bed full of snacks, water and a big bottle of hand sanitizer.
Clatterbuck and Meng drove through suburban neighborhoods in their small SUV. They walked past rose bushes to knock on the door of a home in Lilburn where they were looking for a 19-year-old voter. Her dad answered and promised to call her at college.
PATHS TO VICTORY: How Trump or Joe Biden could win the presidency
Paths to victory: How Trump, Biden could win election
Other problem ballots were cast by people not listed on the voter rolls who will need to explain why. They must correct, or "cure," their ballots by the deadline for the votes to count.
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No one knew how many flawed ballots needed to be fixed. Each of the state's 159 counties keeps its own tally.
Cobb County Republican Party Chairman Jason Shepherd sent out a call Thursday for volunteers to help the state party, saying Republicans were trying to fix provisional ballots. State GOP Political Director Joe Proenza referred comment to a Trump campaign spokesperson who did not respond to an email.
Gabriel Sterling, who has overseen the implementation of Georgia's new electronic voting system, said the state's counties have been working diligently to finish tabulating results. He emphasized his confidence in the legitimacy of the process. Any evidence-backed complaint will be investigated, he added.
"When you have a narrow margin, little, small things can make a difference. So everything's going to have to be investigated to protect the integrity of the vote," Sterling said.
After each county certifies its vote total, the state will perform an audit before issuing its own certification. Counties must certify their results by Nov. 13, and the state must certify them by Nov. 20.
GA Senate race
Republican U.S. Sen. David Perdue and Democrat Jon Ossoff will face off in a Jan. 5 runoff in Georgia for Perdue's Senate seat, one of two high-profile contests in the state that could determine which party controls the upper chamber.
Libertarian candidate Shane Hazel was able to get enough votes so that neither Perdue nor Ossoff cleared the 50% threshold needed for an outright win.
Thousands of absentee ballots and in-person votes cast early needed to be counted after Election Night passed, forcing a long and tense wait before the race could be called.
Democrat Raphael Warnock and Sen. Kelly Loeffler, the Republican appointed last year after Sen. Johnny Isakson retired, will also compete in a runoff on the same day. The twin races in Georgia are likely to settle which party controls the Senate.
Nationally, the Senate stands at 48-46, with Republicans holding the majority. But Republicans lead uncalled races in Alaska and North Carolina, so the ultimate balance is likely to come down to what happens in the Georgia runoffs.
Both sides promised unlimited funds would flow to the campaigns and onto the airwaves, and they predicted an all-star cast of campaigners for a state that in recent weeks drew visits from Democratic presidential nominee Joe Biden, President Donald Trump, Vice President Mike Pence, Democratic vice presidential nominee Kamala Harris and former President Barack Obama.
The race between Ossoff and Perdue, a close ally of Trump, has been characterized by sharp attack ads but relatively moderate political positions. Both candidates steered toward the middle, vying for a state Trump won handily four years ago, but where swaths of suburbia have shown signs of disillusionment with the president.
The Associated Press and ABC News contributed to this report.