What is a runoff election, and how will it work in Georgia's Senate race?

Washington — While the outcome of critical races in Nevada and Arizona remains unclear, the balance of power in the Senate could very well come down to Georgia, where Democratic incumbent Sen. Raphael Warnock and Republican challenger Herschel Walker will face each other in a head-to-head matchup known as a runoff election next month.

Secretary of State Brad Raffensperger confirmed Wednesday that the Senate race would advance to a runoff on Dec. 6, since none of the candidates on the ballot cleared the 50% threshold needed to declare victory. Libertarian candidate Chase Oliver won 2.1%, denying both Warnock and Walker a majority of the vote and triggering a second election to determine the winner.

The Dec. 6 election will be the second time in less than two years that one of Georgia's Senate candidates has failed to win a simple majority of the vote. In the 2020 election, both Senate races headed to runoffs. Warnock and Democratic Sen. Jon Ossoff ultimately defeated Republican incumbent Sens. Kelly Loeffler and David Perdue, respectively, in the Jan. 5, 2021, contest. The sweep by the two Democrats solidified the party's control of the Senate.