Republicans are fretting that a candidate endorsed by Donald Trump may cost them in their most important state.
Ken Paxton has claimed the nomination as the Republican Senate candidate in Texas, beating long-time incumbent John Cornyn.
His comfortable win this morning over Cornyn comes after Trump threw his support behind Paxton last week after a bitter and expensive primary election.
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But Paxton has been so scandal-prone that it could give Democrats an opening in the conservative state.
As Texas attorney-general, his own staff reported him to the FBI with bribery and corruption accusations.
Paxton then fired the whistleblowers.
He was impeached by the state House of Representatives but kept his job after a vote to remove him failed by a single vote in the Texas Senate.
In 2015, he was arrested while attorney-general and charged with security fraud, paying a $A400,000 fine and doing 200 hours of community service in a deal with prosecutors.
He was also caught on CCTV pocketing another lawyer's $A1400 pen when it had been left behind at a metal detector.
"To call Paxton ethically challenged is to call Jeffrey Dahmer suffering from an eating disorder," Republican senator Thom Tillis said.
"This guy is an empty suit and will do us no service by being in the US Congress."
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His wife Angela filed for divorce last year on "biblical grounds", alleging adultery.
Mrs Paxton, herself a state senator, did not make an endorsement in the election.
Despite his misdeeds, Paxton publicly professes his Christian faith and was a co-founder of a Dallas megachurch in the 1990s.
His deeply conservative views have made him a darling in Texas Republican politics.
He has been a vocal opponent of same-sex marriage, transgender rights and COVID-19 restrictions.
In 2022, he said he would be in favour of recriminalising sex between men.
Making Republicans nervous in Texas is the surprising popularity of Democratic candidate James Talarico.
Talarico is a state representative and former teacher who also speaks of his own Christian faith. He has a masters of divinity from Austin Presbyterian Theological Seminary.
In the first three months of the year, he raised $A37 million for his campaign, more than ten times Paxton did.
But in the past 20 years, Texas has been the prize Democrats can't quite win.
But Trump is so on the nose with voters that it may cost Republicans their crown jewel.
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Voters have turned hard against Trump, with the most pronounced swing among Hispanic Americans. In Texas, 40 per cent of the population is Hispanic.
Trump's endorsement of Paxton came after a battle with Cornyn to win the president's approval.
Both candidates campaigned on their devotion and loyalty to Trump, but Paxton won out in the end.
Texas is the biggest Republican-leaning state in the United States. If Democrats can make the state competitive, it will transform the way presidential elections are run.
The midterm election will take place in November.
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