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Sen. Kelly Loeffler and her Democrat challenger Raphael Warnock will appear in a debate Sunday evening ahead of their Jan. 5 runoff election in Georgia, with the event serving as a potential inflection point in the race with control of the U.S. Senate during the next Congress on the line. 

The debate can be viewed on Fox News Channel Sunday, beginning with pre-debate coverage at 6:45 p.m. ET. The event is hosted by the Atlanta Press Club (APC) in partnership with Georgia Public Broadcasting (GPB). 

The Senate race between Loeffler and Warnock is one of two in the state that is now under a much more intense microscope than they were before Nov. 3. Republicans secured 50 Senate seats during the general elections. Democrats won the presidency and brought their total in the upper chamber to 48. 

That means the winners of the Loeffler-Warnock race and the contest between Sen. David Perdue, R-Ga., and Democrat challenger Jon Ossoff will determine whether or not Senate Majority Leader Mitch McConnell, R-Ky., will have an effective veto over much of the Biden agenda or if current Senate Minority Leader Chuck Schumer, D-N.Y., will have the chance to shepherd Biden's priorities through Congress.

APC Debate Committee Chair Maria Saporta recognized that all eyes are on Georgia, saying the debate between Loeffler and Warnock will be the APC's "biggest event ever."

Sen. Kelly Loeffler, R-Ga., (right) and her Democrat challenger Raphael Warnock (left) will participate in a nationally televised debate Sunday (Getty Images)

Sen. Kelly Loeffler, R-Ga., (right) and her Democrat challenger Raphael Warnock (left) will participate in a nationally televised debate Sunday (Getty Images)

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"It really feels like we're at the center of the political universe and will be until Jan. 5," Saporta said in an interview with Fox News. "And it's incumbent upon us to make sure that we look as good as possible."

Loeffler and Warnock are in a special election to replace former Georgia Sen. Johnny Isakson, a Republican, who retired last year. They each survived what was effectively a primary race on Nov. 3, securing the most votes by any candidate in their party and advancing to a head-to-head runoff. This will be Loeffler and Warnock's first and likely only head-to-head debate. 

Ossoff will also make an appearance Sunday. Perdue declined to debate Ossoff so the challenger will have his own forum ahead of the Warnock-Loeffler debate. 

Here's what to expect in what may be the most high-profile debate for a nonpresidential race in American history. 

Rules

The APC debates have rather unique rules that some viewers may not be used to. 

There is one moderator and two "panelists." The panelists ask the questions while the moderator's job is to control the overall flow of the debate and determine when a rebuttal is appropriate. 

In addition, the candidates are afforded the opportunity to ask questions to each other, something that Saporta believes adds value to the event. 

Georgia Democratic candidate for U.S. Senate Jon Ossoff grabs signs to give out during a drive-thru yard sign pick-up event on Wednesday, Nov. 18, 2020, in Marietta, Ga. Ossoff and Republican candidate for Senate Sen. David Perdue are in a runoff election for the Senate seat. (AP Photo/Brynn Anderson)

Georgia Democratic candidate for U.S. Senate Jon Ossoff grabs signs to give out during a drive-thru yard sign pick-up event on Wednesday, Nov. 18, 2020, in Marietta, Ga. Ossoff and Republican candidate for Senate Sen. David Perdue are in a runoff election for the Senate seat. (AP Photo/Brynn Anderson)

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"One of the best parts of our debates, I tend to think, is we allow candidates to ask questions to each other as well," she said. "So that also gives the candidates an opportunity to really, instead of just attack ads on TV to, you know, look their opponent in the eye and say, 'Hey, what about this?' And then the opponent has the opportunity to respond."

The APC has a policy, according to Saporta, that they will not cancel debates just because one candidate does not agree to it. In such a case – like what the APC hoped would be an Ossoff-Perdue debate – its policy is to leave an empty podium to represent the candidate who has opted not to appear. 

"The empty podium speaks volumes about, you know, our political leaders. In my mind, it's our strongest lever we have had to get people to participate in our debates," Saporta said. 

Moderator and panelists

FOX 5 Atlanta anchor Russ Spencer will serve as the moderator Sunday. Saporta praised the experienced local TV journalist in her conversation with Fox News this week. 

"We wanted a moderator and panelists who had done our debates before because it's so important and we try and get some of the best people in the business to do it," she said. "Russ has been a great moderator for us in the past."

FILE - In this Nov. 20, 2020, file photo Sen. David Perdue, R-Ga., takes the stage before Vice President Mike Pence during a Defend the Majority Rally in Canton, Ga. (AP Photo/Ben Gray, File)

FILE - In this Nov. 20, 2020, file photo Sen. David Perdue, R-Ga., takes the stage before Vice President Mike Pence during a Defend the Majority Rally in Canton, Ga. (AP Photo/Ben Gray, File)

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She recalled a previous race when a gubernatorial candidate was not going to show up for a debate. Spencer, she said, convinced FOX 5 to air a one-person debate, which ultimately resulted in that candidate who had planned on holding out showing up.  

Saporta added: "We try and pick people who are good representatives of the journalism community here. Part of the job of the Atlanta Press Club is to let the public know the role that strong journalists play in our society. And this is a great way for them to kind of see the power of asking questions."

The panelists for Sunday are Lisa Rayam, Atlanta NPR "Morning Edition" host and senior producer, and Greg Bluestein, Atlanta Journal-Constitution political reporter.

Saporta noted that the panelists are given "total freedom" on what questions to ask and permission to follow up as they believe is necessary. 

No love lost

In a year when personal attacks, invective and base mobilization have been at the center of American politics, the Georgia Senate races have been particularly bruising. 

Perdue has accused Ossoff of making money off of China and Al-Jazeera. Ossoff has accused Perdue of using his Senate position for financial gain. Loeffler has leveled attacks against "Radical Raphael." Warnock is accusing Loeffler of "profiting off the pandemic."

Warnock has a long history as a vivacious pastor before he decided to run for office, and Loeffler has seized on a number of less-than-tactful comments to paint Warnock as a member of the far left. 

Besides that, Loeffler has specifically attacked Warnock over his past association with the controversial Rev. Jeremiah Wright and over a 2002 arrest of Warnock for allegedly obstructing a child abuse probe. 

Raphael Warnock, a Democratic candidate for the U.S. Senate, speaks during a campaign rally on Sunday, Nov. 15, 2020, in Marietta, Ga. Warnock and U.S. Sen. Kelly Loeffler are in a runoff election for the Senate seat. (AP Photo/Brynn Anderson)

Raphael Warnock, a Democratic candidate for the U.S. Senate, speaks during a campaign rally on Sunday, Nov. 15, 2020, in Marietta, Ga. Warnock and U.S. Sen. Kelly Loeffler are in a runoff election for the Senate seat. (AP Photo/Brynn Anderson)

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"I was a youth pastor 25 years ago at a church. I had nothing to do with that program. The sad thing is they know it. But if you don't really have an agenda for working families I guess you have to distract working families," Warnock said at a press conference when asked about the allegations regarding the child abuse probe. 

Warnock, meanwhile, has attacked Loeffler over stock sales she made ahead of the economic crisis that came with the coronavirus pandemic. 

But in early June an ethics probe dismissed a complaint against Loeffler, as well as Sens. Dianne Feinstein, D-Calif., and Jim Inhofe, R-Okla., who were under similar scrutiny. 

Loeffler, whose net worth is well over $150 million, said an adviser made the trades in question and she had no input in them. She sold between $1.2 million and $3.1 million in stocks, representing just a fraction of her net worth. 

Sen. Kelly Loeffler, R-Ga., who is running for reelection, wears a Trump mask as she speaks to the media at Cobb County International Airport on Election Day, Tuesday, Nov. 3, 2020, in Kennesaw, Ga. (AP Photo/Branden Camp)

Sen. Kelly Loeffler, R-Ga., who is running for reelection, wears a Trump mask as she speaks to the media at Cobb County International Airport on Election Day, Tuesday, Nov. 3, 2020, in Kennesaw, Ga. (AP Photo/Branden Camp)

Warnock has also attacked Loeffler over the fact she has associated with highly controversial Congresswoman-elect Marjorie Taylor Greene, R-Ga., who has been criticized largely for previous comments supporting the QAnon. Greene has since repudiated QAnon, a conspiracy theory centered on the baseless belief that President Trump is waging a secret campaign against enemies in the "deep state" and a child sex trafficking ring.

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Ossoff, meanwhile, is expected to slam Perdue over stock trades he's made not only in the wake of the pandemic but of stocks for companies that have fallen under his purview on his various Senate committees. A recent New York Times report revealed that Perdue may have had more personal involvement in his prolific stock trading than his campaign has let on, saying in response to attacks on the senator that his trades are made by an outside adviser. 

Despite the fact that some vitriol is certainly expected Sunday, Saporta said she is confident that the debate won't devolve into something resembling the first presidential debate. 

"The first presidential debate was something that no one was prepared to face. But we've had several debates since and I would say they were maybe not as civil ... as I wanted them to be. But the moderators were able to control the conversation," she said. 

Debate challenges

While Loeffler is debating Warnock on Sunday, she has yet to agree to the two additional debates that the Democrat has challenged her to, something Warnock noted when she first accepted the APC debate last month. 

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"I hear you're ready to debate, @KLoeffler. Assume that means I'll see you December 6th at the Atlanta Press Club, and twice more so Georgians know who will work for them," Warnock said. 

Ossoff, meanwhile, has challenged his opponent to a potentially unrealistic six debates. Perdue's campaign has accused Ossoff of lying in the two previous debates the candidates have had. 

"We’ve already had two debates in this election. In each, Ossoff lied repeatedly, and of course the media failed to hold him accountable," Perdue communications director John Burke said in a previous statement.

"He refused to talk about the issues and could not defend his radical socialist agenda. If Ossoff wants to keep lying to Georgians on TV, he will have to use his out-of-state money to pay for it," Burke continued. 

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As the high-profile campaign pushes on, big names – including the presidents and vice presidents from the previous two administrations – have gotten involved in Georgia. 

President-elect Joe Biden on Friday took to Twitter to urge people in Georgia who are not registered to vote to do so by Monday’s deadline.

The tweet came as Vice President Pence was on his way to Georgia for a rally for Perdue and Loeffler Friday. Former President Obama appeared in a virtual event with Ossoff and Warnock on the same day. President Trump then appeared in a rally on behalf of the Republicans Saturday. 

Meanwhile, a bevy of current and former politicians – from senators to former presidential candidates and more from both parties – have already made their pilgrimages to "the center of the political universe" and many others are likely to do so before Jan. 5. 

Fox News' Marisa Schultz and Ronn Blitzer contributed to this report.