Warnock, whose victory was announced by American television networks CNN, CBS and NBC, is a pastor at the same church where Martin Luther King preached until he was assassinated in 1968 in Atlanta during the African-American civil rights movement.

"Tonight, we demonstrated that with hope, hard work and people on our side, anything is possible," Warnock told supporters in a virtual speech. The other Democrat up for election, Jon Ossoff, was also ahead in the count against outgoing Republican Senator David Perdue when 95 percent of the votes were counted, according to the Associated Press (AP) news agency. Ossoff, 33, could become the youngest Democratic senator since Joe Biden, elected in that state in 1973.

If the election of the two Democrats is confirmed, Joe Biden's party would strengthen its victory and could gain control of the Senate, in what would be a further setback for President-in-Office Donald Trump, who still does not concede defeat in the 3 November election.

With a double victory in Georgia, Democrats would get 50 seats in the Senate, the same amount as the Republicans. But, as provided for in the Constitution, future Vice President Kamala Harris would have the power of the final vote, swinging the advantage in favour of the Democrats.

Galvanised by Joe Biden's victory in that conservative southern state, the first since 1992, Democrats were able to mobilize voters, particularly African Americans, the key to any Democratic victory. More than three million voters were able to vote in advance, representing about 40% of those registered in Georgia, a record number in Senate elections in that state.

For independent Cook Political Report analyst Dave Wasserman, this election night reminded him of the midterm elections. "That's what we saw in 2018: many Trump voters just don't mobilize when Trump isn't on the ballot paper," he wrote on Twitter. Biden's former campaign manager Rufus Gifford also wrote on Twitter, "I never thought we were going to win this Georgia election." "Thank you very much, Donald Trump," he joked.