Ashton Hurn has been soundly endorsed as South Australia's new Liberals leader days after Vincent Tarzia quit the role.
Ms Hurn is the party’s third leader in less than 18 months.
“My colleagues unanimously supported me to be their leader, to take the party to the next election, which is just 103 days away,” she said on Monday.
The 34-year-old is now one of five women leaders of the Liberal party at federal, state or territory level.
Mr Tarzia announced he was stepping down on Friday, 16 months after replacing disgraced MP David Speirs.
“I'd like to take this moment just to sincerely thank our former leader, Vincent Tarzia, for his dedication and his service … he's done a fantastic job, and we thank him sincerely for his service," Ms Hurn said.
She said the party had an "absolute mountain to climb" to win the state election in March.
"But my team and I are absolutely committed to making sure that we get to work for the people of South Australia, and that we provide them with a real choice at the next election," Ms Hurn said.
“We are energised, we are focused, and I'll be outlining what the choice is for the people of South Australia - there's a lot of work to be done.”
Mr Tarzia, who was elected leader in August 2024, faced weeks of speculation the party was pushing for Ms Hurn to take over.
Polls suggest the Liberals face an electoral drubbing with Labor Premier Peter Malinauskas among the nation's most popular leaders.
Ms Hurn, who is the Member for Schubert, was born, raised and educated in the Barossa Valley.
Her farming family produces grapes and sheep.
"Our family, like many across our region, has always strived to make a contribution to life in the Schubert community whether through local sport clubs, agriculture, emergency services, community groups, the church or local government," she writes in a biography on her website.
Mr Tarzia is the third state Liberal to lose the leadership in as many weeks.
Brad Battin was replaced as Victoria's opposition leader by Jess Wilson in mid-November, while Kellie Sloane took over from Mark Speakman in NSW days later.
Ms Hurn also joins federal Opposition Leader Sussan Ley and Northern Territory Chief Minister Lia Finocchiaro as the five female Liberal leaders - understood to be a record for the conservative party.
Mr Tarzia on Friday said no colleague had pushed him but "there's a reason why they say it is the worst job in politics".
In June, a YouGov poll showed Mr Malinauskas leading Mr Tarzia as preferred premier by 72 to 14 per cent.
Mr Speirs stepped down as Liberal leader in August 2024, saying he was tired of speculation over his leadership.
He was later charged with supplying drugs and pleaded guilty to the charges in March.
Liberal and former independent upper house MP Frank Pangallo indicated he planned to nominate for the deputy leadership.
Current deputy leader Josh Teague declared on Friday he intended to continue as deputy.
The outcome of that vote has not yet been announced.
