President Trump’s preferred candidate for governor of Georgia won the Republican nomination Tuesday, setting the stage for a marquee November showdown encapsulating the divisions that have deepened during his presidency.

Secretary of State Brian Kemp, an immigration hard-liner who won Trump’s support less than a week before the vote, defeated Lt. Gov. Casey Cagle in a runoff that resonated loudly beyond the state’s borders. Kemp led Cagle by more than 2 to 1, with most of the votes tallied.

“We had the momentum in this race, but those endorsements by the president and the vice president poured gasoline on the fire,” Kemp said in his victory speech.

Kemp advances to a showdown against Democratic Party nominee Stacey Abrams, who, if she wins, will be the first female African American governor of any state. The victory by Kemp instantly turned the general election race into a sharp contrast capturing the cultural, racial and political divides that have gripped the country in the Trump era — all in a rapidly diversifying state.

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In a morning tweet, Trump congratulated Kemp on his “very big win” and launched a broadside against Abrams, calling her “crime loving” and “weak” on the military, among other things.

Abrams soon fired back on Twitter, saying she was “proud to join the company” of three other Democrats — Virginia Gov. Ralph Northam, Sen. Doug Jones (Ala.) and Rep. Conor Lamb (Pa.) — whom Trump had “campaigned against all the way to victory.”

Kemp’s victory served as the latest indication of Trump’s dominance in the Republican Party. His endorsement has proved to be a valuable commodity in primaries from the Deep South to the Northeast in recent months.

In Georgia, however, Republicans were left to ponder whether Trump was strengthening the party’s hand ahead of the November election or weakening it. Kemp ran as a Trump-style conservative in a state where the president only narrowly eclipsed the 50 percent mark in 2016. The president’s move put him at odds with many Republican elected officials, including outgoing Gov. Nathan Deal, who backed Cagle.

Cagle conceded the race to Kemp just 90 minutes after polls closed. “I committed to him my full, undivided support,” he said.

As voters headed to the polls Tuesday morning, Trump reiterated his choice, tweeting: “Today is the day to vote for Brian Kemp. Will be great for Georgia, full Endorsement!”

The president first gave his political blessing to Kemp last Wednesday, backing the candidate running as a self-described “politically incorrect conservative .” Over the weekend, Vice President Pence flew to the state to campaign for Kemp, arguing that he would “bring the kind of leadership to the statehouse that President Donald Trump has brought to the White House.”

The White House imprimatur came as a blow to Cagle, the longtime favorite for the nomination. He finished first in the May 22 primary, but his edge faded in a contest that was shaped by embarrassing audio recordings, accusations of “fake news” and Trump’s involvement.

As he navigated his way through the crowded primary, with rivals tagging him as the “establishment” candidate, Cagle made moves to appease the right, including a fight to punish Atlanta-based Delta Air Lines for its criticism of the National Rifle Association, as well as support for a tax break for private schools in an effort to weaken another candidate for governor.

That became a genuine controversy in June, when conservative gubernatorial challenger Clay Tippins released a recording of Cagle admitting that he had backed the measure specifically to hurt a third candidate, Hunter Hill.

“It ain’t about public policy. It’s about . . . politics. There’s a group that was getting ready to put $3 million behind Hunter Hill,” Cagle said on the recording. “Is it bad public policy? Between you and me, it is.”

Cagle began to dip in the polls after that recording was aired; Hill would go on to endorse Kemp as the candidate who “won’t sell public policy to the highest bidder.” And Tippins wasn’t done, wounding Cagle again with audio of the front-runner saying that Kemp was running to be the “craziest” candidate in the race.

“It sounds like Casey Cagle’s gotten like Hillary Clinton,” Kemp told reporters this month. “I would ask all those crazies to vote Brian Kemp for governor in the Republican runoff.”

Kemp has eagerly waded into the culture wars in his campaign, running ads bragging that liberals did not like it when he stood for the national anthem or displayed his guns.

In perhaps his most famous spot, released before the first round of voting, Kemp boasted about having a big truck — “just in case I need to round up criminal illegals and take them home myself.”

Cagle fought back by portraying himself as the true conservative in the race. In his final attack ad, he accused Kemp, who has been secretary of state for eight years, of “20 years of failure.” In another ad, Cagle was pictured rallying a crowd of conservatives — a few wearing “Make America Great Again” caps — against the negative stories.

“Dirty tricks and fake news are what we’ve come to expect,” Cagle said. “I’ll never apologize for outlawing sanctuary cities or for stopping liberals from taking the values that make our country great.”

Georgia Republicans have held the governor’s mansion since 2003, with legislative majorities that have made Democrats largely irrelevant in state politics. But the smash-mouth nature of the contest has emboldened Democrats, who think that the GOP’s race to the right will alienate the suburban voters who are drifting away from the party in the Trump era.

“The race for #GAGov may change, but our values never will,” Abrams tweeted after Kemp’s win. “Service, faith & family guide our vision for GA: Affordable health care. Excellent public schools for every child. An economy that works for all.”

Abrams has raised a hefty $6 million for the race — nearly $3 million of it since winning the primary. Trump’s 50.44 percent share of the vote in the 2016 election was the lowest for a Republican presidential nominee in two decades. Democrats have increased their share of the vote since then in local elections.

A former minority leader of the Georgia House, she won the Democratic primary while surrounding herself with leaders representing women, labor, the LGBT community and causes on the left — predicting at one rally that a rising coalition of minorities and liberal whites would “turn the state of Georgia, and the nation, blue again.”

Georgia’s Hispanic population has grown to nearly 10 percent of the state’s, according to a recent Census Bureau estimate. African Americans make up nearly a third of the state’s population.

Kemp and fellow Republicans on Tuesday started accelerating efforts to tie Abrams to national Democratic figures, including former presidential nominee Clinton. Their strategy is in line with the GOP’s playbook in other states that Trump won.

Further down the ballot Tuesday, Democrats were picking nominees in two suburban Atlanta congressional districts that were crafted to elect Republicans but swung away from the president’s party in 2016.

In the 7th Congressional District, former congressional aide Carolyn Bourdeaux defeated education company chief executive David Kim for the right to challenge Rep. Rob Woodall (R). In the 6th Congressional District, where first-time candidate Jon Ossoff lost a close special election last year, gun-control activist Lucy McBath defeated Kevin Abel.

Until 2016, neither district was particularly competitive. While Rep. Karen Handel (R) defeated Ossoff in the 6th District, Trump won just 48.3 percent of the vote there and just 51.1 percent in the 7th District — down from the 60 percent that Mitt Romney had won in both districts in 2012.

John Wagner contributed to this report.