EXCLUSIVE: Former Sen. David Perdue filed Federal Election Commission paperwork Monday to become a candidate to run for Senate in 2022, Fox News has learned.

Perdue, who lost re-election to Sen. Jon Osoff, D-Ga., during Georgia’s Senate runoff election on Jan. 5, filed FEC paperwork on Monday evening, designating a "principal campaign committee" titled: "Perdue for Senate."

A source familiar told Fox News that Perdue would not be running for his old seat, as it is not up for re-election, but rather the seat now held by Freshman Sen. Raphael Warnock, D-Ga.

Warnock defeated Sen. Kelly Loeffler, R-Ga., who was appointed by Georgia Gov. Brian Kemp.

Perdue has not formally announced his candidacy for 2022, but the filing of paperwork on Monday is a key step in that direction, a source familiar told Fox News, saying the former senator will be making a final decision in the weeks ahead. 

The source told Fox News that Perdue is leaning toward running. 

Fox News has also learned that Perdue's filing comes as Herschel Walker's name had been increasingly mentioned in Republican circles as a potential 2022 Senate candidate in Georgia. Walker has been a major supporter of former President Trump. 

Also, earlier this month, former Rep. Doug Collins, another major Trump supporter in Georgia, and who ran in the 2020 special election against Loeffler, also was seriously mulling a 2022 Senate bid in the state. 

"I think this would freeze the field," a veteran GOP strategist in Georgia said of the filing by Perdue. "The field is now officially frozen until David says he’s in or he’s out." 

The strategist told Fox News that if Perdue ends up launching a 2022 campaign, Collins would not run.

Fox News' Paul Steinhauser contributed to this report.