Just weeks after the most pivotal US presidential election in this century, early in-person voting began Monday in Georgia ahead of another highly-anticipated political moment: twin runoff races in the state that will determine the balance of power in the Senate.

The southeastern state’s January 5 runoffs have garnered national attention as the outcome will help determine how much of President-elect Joe Biden’s ambitious political agenda can get through Congress and into law.

While Democrats need to flip both seats in order to seize Senate control, Republicans need only one to maintain their majority.

Members of President Donald Trump’s party have framed Georgia as must-win races, with the state forming the last line of defence against what they describe as a radical, left-wing agenda.

Biden was declared the winner of the November 3 election by popular vote, becoming the first Democrat to win Georgia since 1992.

Democratic organizers point to Biden’s win as proof that enough votes exist to flip the Senate seats in a state that has tilted Republican for decades but whose demographics are shifting.

Trump has refused to accept the election outcome, repeatedly stating without evidence that it was “rigged” and that results in swing states that backed Biden should be overturned.

The president’s unprecedented effort to subvert the results has failed, and the Electoral College began voting on Monday to formally recognize Biden as the next US president.

Trump has inserted himself in the Georgia showdown, campaigning for the two Republican senators, Kelly Loeffler and David Perdue, on December 5.

But his repeated false accusations of massive election fraud have complicated Republican messaging to inspire the party’s base to vote, particularly if Trump supporters believe the president’s unfounded claims that the process is rigged.

Trump nevertheless ramped up his rhetoric, calling Georgia’s Republican governor a “clown” overnight for not maintaining more vigorous election oversight and warning that January 5 “could be a bad day” for Loeffler and Perdue.

Biden travels to the state on Tuesday to campaign on behalf of Democratic challengers Jon Ossoff and Raphael Warnock.

“Today’s the FIRST day of early voting, so put your shoes on Georgia, and go vote,” tweeted Warnock, a reverend at a renowned Black church in Atlanta.

In nearby Sandy Springs, a line of voters — most of them masked to guard against the COVID-19 — snaked out of the North Fulton Service Center Monday as residents cast ballots on day one of a three-week stint of in-person voting.

Republican incumbents meanwhile are engaging in a delicate two-step of being aligned with Trump, while seeking to rally Republican voters by warning that so much is at stake in the Senate.

“Georgia is the firewall to socialism,” Loeffler told Fox News on Monday. “We have to hold the line here, not just for Georgia, but the entire future of the country rests on these races and we have to hold the Senate majority.”