Raffensperger held a lead of more than 57,000 votes, but about 72,000 absentee ballots were still outstanding as of Tuesday night. Those ballots will be counted if they were postmarked by Tuesday and received by election officials by this Friday.
Barrow didn’t concede the race.
"This has been a highly contested election," Barrow said. "However, all of the absentee votes have not yet been counted. ... Therefore, in order to make sure that every voice is heard, we need to make sure that every vote is counted. I'll wait for the remaining ballots to come in — and for them to be counted."
In the race for Public Service Commission District 3, incumbent Republican Chuck Eaton was leading Democrat Lindy Miller, a businesswoman and former Deloitte executive. Eaton is seeking a third six-year term on the regulatory body.
The Associated Press called the races for both Raffensperger and Eaton on Tuesday night.
The campaign for secretary of state focused on voting rights and integrity following complaints about voter purges, malfunctioning voting machines and long lines.
The winner will take over the job previously held by Republican Brian Kemp before he won last month’s election for governor against Democrat Stacey Abrams.
Raffensperger, a state House representative and engineering firm CEO, emphasized fighting voting fraud, which is rare in Georgia in part because voters have to show photo ID. He would uphold regular voter registration cancellations and strict voter ID laws to ensure only U.S. citizens can vote.
Barrow, a former U.S. congressman and attorney, would push for changes in Georgia elections to ensure fairness and accuracy. He said it shouldn’t be so easy for Georgians to lose their right to vote after more than 1.4 million registrations were canceled since 2012, often because they hadn’t participated in a recent election.
Both candidates support replacing Georgia’s electronic voting machines with a system that includes a verifiable paper trail, but they disagree on the best option.
Raffensperger favors using touchscreen machines to print ballots to avoid human errors, while Barrow supports hand-marked paper ballots to directly reflect voters’ choices.
The Public Service Commission race has focused on the viability of Georgia Power’s nuclear expansion project at Plant Vogtle and diversification of the state’s energy mix.
The hotly contested election attracted outside money to boost the candidate's visibility in the election, with a Washington-based pro-nuclear power group injecting more than $1 million toward an advertising campaign supporting Eaton.
Miller called the last-minute donation an attempt to “buy the election.”
The PSC is tasked with regulating investor-owned electric and natural gas companies operating in the state. It decides how much in rates these companies charge their customers and also approves the state’s energy plans.
Besides the two statewide runoffs, a redo election for the Georgia House of Representatives was held in North Georgia.
The second election was no clearer than the first, with Chris Erwin holding a three-vote lead after Election Day votes had been counted. But absentee ballots can still be added if they’re returned before the end of the week.
Erwin appeared to win the original May 22 GOP primary election over state Rep. Dan Gasaway of Homer by 67 votes, but a judge ordered a new primary after dozens of voters were given the wrong ballots. Erwin is a construction company’s business director and a former Banks County school superintendent. No Democrat ran in the general election, so the primary winner will fill the legislative seat.
House District 28 covers all of Banks and Stephens counties, as well as about half of Habersham County.
Staff writer Anastaciah Ondieki contributed to this article.
For the latest results and more details from Tuesday's runoff election, go to AJC.com.