Factbox: What is at stake in Georgia's U.S. Senate runoff?

Democratic candidate U.S. Senator Raphael Warnock and Republican U.S. Senate candidate Herschel Walker attend midterm election campaign events in Atlanta and Hiram, Georgia, U.S., November 8, 2022 and November 6, 2022 in a combination of file photos REUTERS/Bob Strong/Jonathan Ernst/File Photo

WASHINGTON, Dec 5 (Reuters) - For the second time in less than two years, a U.S. Senate race in Georgia will go to a runoff - this time between incumbent Democrat Raphael Warnock and his Donald Trump-backed Republican challenger Herschel Walker.

As Election Day neared, Georgia election officials reported heavy turnout in early voting. The Dec. 6 vote will not determine whether President Joe Biden's Democrats hold control of the Senate, where they have already secured enough seats to maintain their razor-thin majority.

Nevertheless, there is a lot at stake for both parties:

MORE BREATHING ROOM FOR DEMOCRATS

Democrats held the narrowest possible majority for the past two years in the 50-50 Senate, where Vice President Kamala Harris gave them the tie-breaking vote. That's led to plenty of headaches for Majority Leader Chuck Schumer as two maverick members of his party - Joe Manchin and Kyrsten Sinema - repeatedly blocked some legislative maneuvers.

A victory by Warnock would mean that Schumer could lose the support of one member of his caucus and still win floor votes. But he may have less opportunity for flashy moves, with Republicans holding a narrow majority in the House of Representatives.

If Walker is victorious, Schumer would be right back to where he has been the past two years, needing to cajole every single one of his senators to go along or potentially suffer a defeat.

Both Manchin and Sinema have had outsized roles in 2021 and 2022 on some of Biden's most prized initiatives, such as COVID-19 relief and legislation related to climate change and prescription drug costs.

SENATE COMMITTEES

Because of the 50-50 Senate divide, committee memberships are currently doled out evenly between Democrats and Republicans. These committees oversee a range of federal programs, from the military and agriculture to homeland security, transportation, healthcare and foreign affairs.

Tied votes in committees block legislation and presidential appointments, at least temporarily, from advancing to the full Senate. It takes time-consuming procedural maneuvers to break the committee deadlock so that the full chamber can pass bottled-up bills and nominations.

A Warnock win would give Democrats at least one more member on each committee than Republicans, making it harder for Republicans to stand in the way of Biden's agenda.

That could also provide Democrats with a stronger counter-balance to House Republicans, allowing Senate committees to advance more liberal legislation and nominees that, in turn, could help energize their core voters in the 2024 elections.

ALL EYES ON 2024

Democrats will face a daunting task in holding onto their majority in the 2024 elections, when they will be defending 21 seats to Republicans' 10. One-third of Senate seats are up for election every two years.

Two of the seats set to be contested in 2024 are in Republican-leaning states West Virginia, where Manchin is up for reelection, and Montana, where Jon Tester faces voters. Another five are in the swing states of Ohio, Pennsylvania, Nevada, Wisconsin and Arizona, all of which will also be in play during the presidential election. Given the chamber's narrow divide, the Georgia seat could be a needed bulwark.

SIX YEARS, NOT TWO

Warnock was elected to the Senate in early 2021 to fill the remaining two years of the late Republican Johnny Isakson's term after he resigned at the end of 2019 for health reasons.

If Warnock manages to defeat Walker, he will put the seat in Democratic hands for six years - a full Senate term - at a time when the party will have to battle to hold its majority status.

A Walker win would give national Republicans a boost, having seen their standing in the state of Georgia erode in favor of Democrats over the last few years. A Warnock victory could indicate that Democrats are making inroads in places where they have had difficulties gaining traction in the past.

Reporting by Richard Cowan; Editing by Scott Malone and Rosalba O'Brien

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