US former Attorney General Jeff Sessions has failed to secure a majority in his efforts to reclaim his old Senate seat in Alabama.
Mr Sessions, who was often criticised by President Donald Trump before being sacked in 2018, is trailing former football coach Tommy Tuberville.
Unlike Mr Sessions, Mr Tuberville has remained a fervent Trump supporter.
Another former Trump aide, his White House doctor Ronny Jackson, is also facing a run-off in Texas.
Mr Jackson, a retired Navy rear admiral, has Mr Trump’s support in his bid to be elected to the House of Representatives. He trails Josh Winegarner, a cattle lobbyist, in the Republican primary in Texas.
A reminder of the Sessions-Trump bust-up
Mr Sessions, 73, had held the reliably Republican Senate seat in Alabama for 20 years before joining Mr Trump’s team as the president’s first attorney general.
He has often come under fire from Democrats over his hard-line views on immigration and allegations of racist remarks.
But the early Trump supporter fell foul of the president when he refused to oversee the investigation into allegations of Russian interference in the 2016 presidential election.
Mr Trump has not endorsed Mr Sessions – or his rival Mr Tuberville, 65, for the run-off due on 31 March.
The winner will face Senator Doug Jones, who won the seat Mr Sessions vacated amid backlash for his Republican opponent, Roy Moore, who was accused of sexually assaulting underage girls. Many say Mr Jones is the most endangered Democrat up for re-election in November.
Republicans currently control the Senate.
What about Mr Trump’s former personal physician?
Mr Jackson, 52, worked as White House physician from 2006 to 2018.
He was famously known for his report on the president’s health and mental well-being, including a mention of Mr Trump’s “incredible genes”.
Mr Jackson told reporters that the president could live to the age of 200 if his diet improved.
He came under more scrutiny in 2018 when he was nominated by President Trump to lead the US Department of Veterans Affairs.
His name was withdrawn shortly afterwards, amid accusations of questionable drug prescriptions, drunkenness and wrecking a government vehicle – allegations the doctor condemned as “baseless”.
The 26 May primary run-off will decide the candidate to replace retiring Republican Mac Thornberry, who was first elected to the House in 1994.