ATLANTA — Less than a year after losing the presidency, Donald Trump has set out to reshape the GOP in his image across the nation's top political battlegrounds, sparking bitter primary battles that will force candidates and voters to decide how much to embrace Trump and his grievances. 

But nowhere is his quest more consequential than Georgia.

Trump has inspired a slate of loyalists to seek statewide office in the Southern swing state, and as of Monday, that group included former Republican Sen. David Perdue, who formally launched a challenge against Republican Gov. Brian Kemp. The move marked a rare, serious primary threat to a sitting governor, bucking the wishes of GOP leaders in Washington and ensuring months of Republican infighting in a state where the party is trying to restore its dominance. 

"It is going to be a political civil war here in Georgia," current Lt. Gov. Geoff Duncan, a Republican and frequent Trump critic who is not running for reelection, told The Associated Press. "It's all avoidable if we just act like adults and move on. But that's not reality at this point."

It's not just Georgia. 

Tension between Trump and what's left of the Republican establishment is defining primaries for Senate and governor across dozens of states — including Arizona, Massachusetts, North Carolina, Ohio and Pennsylvania — months before the first ballots are cast next spring and summer. With President Joe Biden's approval numbers sagging, political headwinds from Washington suggest that Republicans could make major political gains in 2022 — if the GOP can get out of its own way.

Trump's interest in a third presidential bid in 2024 ensures he will be the face of the Republican Party for the foreseeable future. 

Look no further for a cautionary tale than Georgia, an evolving swing state where demographic shifts of recent years have given Democrats a path to power. Biden narrowly defeated Trump here last fall and, after Trump falsely claimed widespread election fraud, Democrats seized victory in two Senate runoff elections in January that gave them control of the Senate. 

Ever since, the former president has battered the state officials who certified the election results — Kemp chief among them — with an fierce torrent of political attacks. 

Trump's chief problem with Kemp has little to do with substantive policy; he's working to oust the governor simply because he refused to support Trump's fight to overturn the 2020 election. 

The former president called Kemp "a very weak governor" in a statement endorsing Perdue on Monday night, citing nothing specific in his opposition to the sitting governor save his position on "election integrity."

"Most importantly," Trump said of Kemp, "he can't win because the MAGA base — which is enormous — will never vote for him." 

Trump also boosted Republican former football star Herschel Walker in the GOP's push to unseat Democratic Sen. Raphael Warnock, betting on an untested and unvetted professional athlete in a Republican primary against state Agriculture Commissioner Gary Black. He is also backing like-minded candidates in Republican primaries for lieutenant governor and secretary of state, where current Secretary of State Brad Raffensperger is fighting for his political survival.

Nationwide, Trump has endorsed more than 60 midterm candidates so far, including several running against Republican incumbents.

Trump's intervention in the Georgia governor's race is a nightmare scenario of sorts for some Republican strategists, who were already gearing up for a difficult general election contest against former state lawmaker and Democratic voting rights activist Stacey Abrams, who narrowly lost to Kemp in 2018. Abrams formally announced her candidacy last week.

In his announcement video, Perdue said he was running first and foremost to stop Abrams and an "unprecedented onslaught from the woke left." He also parroted Trump's baseless claims about the 2020 election.

"We simply have to be united," said Perdue, who narrowly lost his Senate seat in January. "Unfortunately, today we are divided, and Brian Kemp and Brad Raffensperger are to blame."

Meanwhile, a furious Kemp promised an all-out brawl. Kemp spokesman Cody Hall dubbed Perdue "the man who lost Republicans the United States Senate" and blamed the ousted senator for a list of complaints including inflation, high government spending and cancel culture. 

The Georgians First Leadership Committee, a Kemp-aligned group that can raise unlimited contributions, also attacked Perdue just hours after his announcement in a fundraising email, seizing on the former senator's business record and stock trades while in office. Democratic Sen. Jon Ossoff used similar criticism to defeat Perdue in January's Senate contest.

"This crooked insider and 'America Last' loser is DESPERATE to claw his way back into political relevance," the committee wrote in a fundraising email.

Republicans in Washington and beyond prepared for a nasty and expensive GOP primary, which could ultimately cost tens of millions of dollars and drag Kemp to the right in a state that has moved to the center. So far, Abrams has no primary challengers. 

"While David Perdue and Brian Kemp fight each other, Stacey Abrams will be fighting for the people of Georgia," Abrams top aide Lauren Groh-Wargo wrote on Twitter.

The governor's race reflects GOP divisions playing out across Republican communities this year. 

In Georgia, pro-Trump activists angered by his defeat have flooded local Republican Party meetings, seizing control of the party machinery while dumping some metro-Atlanta county officials deemed insufficiently pro-Trump. 

David Shafer, the state party chairman, has maintained a pro-Trump line. 

Criticized for speaking at Trump's September rally where Trump joined his slate of endorsed candidates, Shafer on Sunday told The Associated Press that the party would be neutral in contested primaries and said he hoped Republican candidates "will focus on their own strengths and how they can assemble a winning coalition."

National Republican leaders are remaining loyal to Kemp. 

Anticipating a Trump-backed challenge from Perdue, the Republican Governors Association vowed to support the incumbent Georgia governor in addition to other sitting Republican governors who have drawn Trump's ire, including Idaho Gov. Brad Little. In helping Republican incumbents, however, RGA Chairman Doug Ducey, the Arizona governor, said his organization would not attack Trump's slate of challengers.

"The RGA follows the 11th Commandment," Ducey said at the group's recent gathering in his state. "We do not speak ill of another Republican."

But Republicans on the ground in Georgia are not likely to play so nice.

Georgia Republican Party official Randy Evans, who served as Trump's ambassador to Luxembourg, argued that Kemp may be so unpopular with the Trump base that he will lose to Abrams even if he survives the primary.

"If the party comes together, Perdue will be the nominee and then he'll go on to be governor," Evans said. "And if the party comes apart, which if the bitterness and divisiveness continues with this kind of rhetoric, then Kemp will be the nominee and Stacey will be the governor."