What is a runoff election? Georgians head to the polls for Warnock v. Walker round two.

Today in Georgia a highly contentious race for United States Senate will finally come to an end. After neither candidate claimed a majority of votes during the Nov. 8 general election, the contest moved to a runoff. For some in the Peach State it feels like Deja-vu, as just two years ago Georgians were asked to head to the polls for two runoff elections that would ultimately determine control of the Senate.

Today its Warnock vs. Walker round two. Sen. Raphael Warnock, the Democratic incumbent, is fighting to keep his seat, hoping to fend off a challenge from GOP candidate Hershel Walker, a former football star who earned the endorsement of former President Donald Trump.

Here's everything you need to know about the runoff election, how it works, and why it was necessary.

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What is a runoff election?

A runoff election is essentially a tiebreaker, it is a special election held after the general election if no candidate claims over 50% of the vote. In this case, another contest is held between the two candidates who garnered the most votes.

Rules for runoff elections can vary state to state.

When is Georgia's runoff election?

Today.

While early voting has already been under way for some time, and plenty of ballots have been cast, the official date for Georgia's runoff election is Tuesday, Dec. 6. By law in Georgia, the runoff takes place just four weeks after the general election.

In those four weeks both Democrats and Republicans have raced to drum up support for their candidates: Reverend Raphael Warnock, the incumbent Democratic Senator, and Hershel Walker, a former football star who is backed by former President Trump.

Prior to this year, a runoff for federal offices was held nine weeks after the general election in Georgia. However, a new bill passed by the state legislature in 2021 shortened that period to four weeks.

This article originally appeared on USA TODAY: What is a runoff election? What's happening in Georgia Senate race