Kari Lake, a Trump-backed Republican who repeated his false claims of election fraud, lost to Democrat Katie Hobbs in the race for governor.
Donald Trump has suffered a further blow after another of the candidates he supported in the US midterm elections lost in Arizona, according to projections.
Republican Kari Lake was beaten in the race for governor of the southwestern state by Katie Hobbs -- the first time a Democrat has been elected to lead the state since 2006.
Kari Lake was one of the most high-profile Republican candidates in last Tuesday's vote, and consistently repeated Trump's false claims of voter fraud in the 2020 presidential election during the campaign.
The former president has been blamed for the Republicans' poor showing in the midterms, including their failure to take control of the US Senate.
The party is still expected to win back the House of Representatives from Democrats but by a much smaller margin than predicted.
Hobbs, who is Arizona's secretary of state, rose to prominence as a staunch defender of the legitimacy of the 2020 election and warned that her Republican rival would be an agent of chaos.
“This was not just about an election — it was about moving this state forward and facing the challenges of our generation,” Hobbs said in a statement declaring victory.
"Arizonans know BS when they see it," Lake said afterwards on Twitter, where she has also suggested there have been irregularities in her own state. During the campaign, the former TV presenter refused to say she would accept the results of her race.
Vote counting had gone on for days since the Tuesday election, as officials continued to tally massive amounts of late-arriving ballots.
When the Republican candidate accused the state’s most populous county of “slow-rolling” the vote count to skew early election results, a local official fired back.
“Quite frankly, it is offensive for Kari Lake to say that these people behind me are slow-rolling this when they’re working 14 to 18 hours” every day, said Bill Gates, the Republican chairman of the Maricopa County board of supervisors.
A one-time Republican stronghold where Democrats made gains during the Trump era, Arizona has been central to efforts by Trump and his allies to cast doubt on Joe Biden’s 2020 presidential victory with baseless claims of fraud.
Trump himself was due to make what he's teased as a big announcement later on Tuesday -- widely expected to be the official launch of this 2024 presidential campaign.
But Republican politicians and voters appear divided -- with some now throwing their support to Florida Governor Ron DeSantis.
Just one other US president has been elected to two non-consecutive terms -- Grover Cleveland in 1884 and 1892.