This combo photo shows the US Democratic challenger in one of the Georgia contests, Raphael Warnock (left), and his rival, Republican Senator Kelly Loeffler. (PHOTOS / AP)

ATLANTA - Democrats won one hotly contested US Senate race in Georgia on Wednesday and pulled ahead in a second, edging closer to control of the chamber and the power to advance Democratic President-elect Joe Biden’s policy goals when he takes office this month.

Democratic challenger Raphael Warnock beat Republican incumbent Kelly Loeffler, TV networks and Edison Research projected. Democrat Jon Ossoff held a narrow lead over Republican David Perdue in the other race, with a final outcome not expected until later on Wednesday.

With 98 percent reporting, Warnock was ahead of Loeffler by 1.2 percentage points, roughly 50,000 votes, while Ossoff led Perdue by more than 12,000 votes, according to Edison Research.

Democrats must win both contests in Georgia to take control of the Senate. A double win for the Democrats would create a 50-50 split in the Senate

The critical races drew an estimated 4.5 million voters - a record for a runoff - along with nearly half a billion dollars in advertising spending since Nov 3 and Monday visits by Republican President Donald Trump and Biden.

Most of the votes remaining to be counted were in counties Biden won in November, with roughly 13,000 votes still to be counted in Democratic-leaning DeKalb County near Atlanta, according to Edison Research estimates.

This combo photo shows US Democrat Jon Ossoff (left) and Republican David Perdue, the candidates in the other Georgia runoff election. (PHOTOS / AP, AFP)

“We were told that we couldn’t win this election. But tonight, we proved that with hope, hard work and the people by our side, anything is possible,” Warnock told supporters in a livestream message before the projection.

“I am going to the Senate to work for all of Georgia, no matter who you cast your vote for in this election.”

Georgia Secretary of State Brad Raffensperger said election officials would take a break overnight but resume counting on Wednesday morning. “Hopefully by noon we’ll have a better idea where we are,” he said on CNN.

Election workers sort and verify absentee ballots for Georgia state's US Senate runoff election at the Beauty P. Baldwin Voter Registrations and Elections Building in Lawrenceville, Georgia, on Jan 5, 2021. (CURTIS COMPTON / ATLANTA JOURNAL-CONSTITUTION VIA AP)

Democrats must win both contests to take control of the Senate. A Democratic sweep would create a 50-50 split in the Senate and give Vice-President-elect Kamala Harris, as president of the Senate, the tie-breaking vote after she and Biden take office on Jan 20. The party already has a narrow majority in the US House of Representatives.

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If Republicans hold onto the Senate, they would effectively wield veto power over Biden’s political and judicial appointees as well as many of his policy initiatives in areas such as economic relief, climate change, healthcare and criminal justice.

Both Biden and Trump campaigned in the state on Monday, underscoring the stakes.

Democratic optimism

No Democrat has won a US Senate race in Georgia in 20 years, but opinion surveys show both races as exceedingly close. The head-to-head runoff elections, a quirk of state law, became necessary when no candidate in either race exceeded 50 percent of the vote in November.

Warnock will become Georgia’s first Black US senator and Ossoff, at 33, would be the Senate’s youngest member if he wins. Perdue is a former Fortune 500 executive who has served one Senate term. Loeffler, one of the wealthiest members of Congress, was appointed a year ago to fill the seat of a retiring senator.

No Democrat has won a US Senate race in Georgia in 20 years. Biden’s narrow statewide win in the Nov 3 election - the first for a Democratic presidential candidate since 1992 - has given the party reason for optimism in a state dominated by Republicans for decades

Biden’s narrow statewide win in the Nov 3 election - the first for a Democratic presidential candidate since 1992 - has given the party reason for optimism in a state dominated by Republicans for decades.

READ MORE: Georgia confirms results in latest setback for Trump

In Smyrna, about 26 kilometers northwest of Atlanta, Terry Deuel said he voted Republican to ensure a check on Democratic power.

“The Democrats are going to raise taxes,” the 58-year-old handyman said. “And Biden wants to give everyone free money - US$2,000 each or something like that for COVID stimulus? Where are we going to get the money?”

Ann Henderson, 46, cast ballots at the same location for Ossoff and Warnock, saying she wanted to break Washington’s gridlock by delivering the Senate to Democrats.

“It’s the social issues - civil rights, racial equality, voting rights, pandemic response,” she said. “If we take it, maybe we can get something done for a change.”

US equity market index futures were broadly weaker as the results turned in favor of the Democrats, signaling stocks could open on the soft side on Wednesday morning. The benchmark S&P 500 e-mini futures contract was down 0.6 percent, while futures tracking the tech-heavy Nasdaq were off by 1.3 percent.

Voters practice social distancing while waiting in line to cast their votes in Georgia state's runoff election inside the gymnasium at Social Circle Middle School, in Social Circle, Georgia, on Jan 5, 2021. (CURTIS COMPTON / ATLANTA JOURNAL-CONSTITUTION VIA AP)

Trump rages

The campaign’s final days were overshadowed by Trump’s continued efforts to subvert the presidential election results.

On Saturday, Trump pressured Raffensperger, a fellow Republican, on a phone call to “find” enough votes to reverse Biden’s victory, falsely claiming massive fraud.

Trump’s efforts to undo his loss - with some Republicans planning to object to the certification of Biden’s win when Congress meets on Wednesday to formally count the presidential vote - have caused a split in his party and condemnation from critics who accuse him of undermining democracy.

At Monday’s rally in Georgia, Trump again declared the November vote “rigged,” an assertion some Republicans worried would dissuade his supporters from voting on Tuesday.

READ MORE: 2020 election again exposes problems with US political polls

His attacks appear to have undermined public confidence in the electoral system. Edison’s exit poll found more than seven in 10 were very or somewhat confident their votes would be counted accurately, down from 85 percent who said the same in a Nov 3 exit poll.

Gabriel Sterling, a top official in the Georgia Secretary of State’s Office, told CNN that - in his opinion - Republican losses would fall on Trump.

“When you tell people your vote doesn’t count, it’s been stolen, and people start to believe that, and then you go to the two senators and tell them to ask the secretary of state to resign and trigger a civil war inside the Republican Party … all of that stems from his decision-making,” he said.