Georgia Republican Governor Brian Kemp won his party's primary vote on Tuesday over a challenger endorsed by Donald Trump, marking the former U.S. president's biggest defeat so far in his effort to play kingmaker ahead of November's midterm elections.

Georgia voters were still waiting to see whether Secretary of State Brad Raffensperger, who was leading in the tally so far, also weathered Trump's bid to oust him over his and Kemp's refusal to try to overturn his defeat in the 2020 election.

Trump had backed Kemp's opponent former U.S. Senator David Perdue, who repeatedly promoted the former president's false claims that he lost in 2020 due to widespread voter fraud. Edison Research called the race for Kemp, who held a commanding 73%-23% lead over Perdue.

Kemp will face Stacey Abrams, a progressive who secured the Democratic nomination on Tuesday. Kemp, who beat Abrams in 2018, sought to paint her as a far-left radical who only saw the governorship as a "stepping stone" to the White House.

"Our battle is far from over," Kemp said in a speech in which he thanked Perdue for pledging his support. "Tonight the fight for the soul of our state begins to make sure that Stacey Abrams is not going to be our governor or the next president."

The night was not a total loss for Trump. His pick for U.S. Senate, former American football star Herschel Walker, easily won the Republican nomination and will now face Democratic U.S. Senator Raphael Warnock on Nov. 8. And in Texas, the Trump-backed Attorney General Ken Paxton defeated state Land Commissioner George P. Bush in a runoff after the March primary.

The political environment has grown increasingly favorable to Republicans in the run up to November's midterms. According to a Reuters/Ipsos opinion poll completed on Tuesday, President Joe Biden's approval rating has fallen to 36%, the lowest level of his presidency, reflecting voter worries over rising inflation.

Republicans are favored to win a majority in the U.S. House of Representatives in November, though analysts say Democrats have a better chance of holding onto control of the Senate.

The loss of either chamber would bring Biden's legislative agenda to a halt and give Republicans the power to launch distracting and potentially politically damaging investigations.

Raffensperger, who rejected a plea by Trump in 2020 to "find" enough votes to alter the outcome, was up 51% to 34% over U.S. Representative Jody Hice, with about 60% of the expected vote counted, according to Edison Research. Raffensperger would need to secure more than 50% of the vote to avoid a runoff.

Endorsed by Trump, Hice has echoed the former president's baseless fraud claims.

Trump has made more than 190 endorsements since leaving office, mostly for incumbent Republicans who face no serious primary opposition.

He has amassed a mixed record in competitive contests. His nominee for U.S. Senate in Pennsylvania, the television host Dr. Mehmet Oz, is in a race still too close to call a week after voting.

KEMP-ABRAMS REMATCH

Kemp's surging campaign has drawn support from some high-profile Republicans who have themselves been targets for Trump's ire, including Trump's former vice president, Mike Pence.

While the result is a reputational setback for Trump, it does not signify a change in the broad Republican support for Trump's policies. Kemp backers have said they like his hard-line on immigration and pro-business stance. During his speech, Kemp touted his record of cutting taxes and drawing investment to the state.

"Everyone always predicts Trump's downfall but here we are today," Marci McCarthy, chair of the DeKalb County Republican Party, said at Perdue's election-night party. "I think President Trump's presence through many candidates today says everything."

Some Republican leaders have expressed concern that Walker's past, including allegations of domestic violence, could hurt his chances in the general election.

Four other states - Alabama, Texas, Arkansas and Minnesota - also held primary elections on Tuesday.

In Alabama, U.S. Representative Mo Brooks, who lost Trump's endorsement after saying it was time to move on from the 2020 election, was among those battling for a Senate seat.

Trump-era White House spokesperson Sarah Huckabee Sanders won the Republican gubernatorial nomination in Arkansas, Edison projected.

In Texas, U.S. Representative Henry Cuellar, a moderate Democrat, was locked in a tight runoff with progressive challenger Jessica Cisneros. Cuellar led 52% to 48% with just over two-thirds of the expected vote counted, according to Edison Research.

Elsewhere in Georgia, Lucy McBath beat Carolyn Bourdeaux in rare a contest pitting two incumbent Democratic U.S. Representatives against one another after Republican lawmakers redrew the state's congressional map.

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