The West Australian Liberals are about to choose a new leader after Mike Nahan announced his resignation, saying the time was right to move on.
Dr Nahan named his deputy Liza Harvey and finance and energy spokesman Dean Nalder as his top picks to succeed him, although health spokesman Sean L'Estrange could also run when the party meets on Thursday morning.
Mrs Harvey has already confirmed she will stand for the leadership position.
"I am definitely nominating ... and at this stage I don't know of anyone else nominating, although that is not to say I will be running unopposed," she told The West Australian.
Mr Nalder could run as her deputy if she is successful.
Mr Nahan, the Michigan-born former state treasurer, said he had planned to review his position halfway through his current four-year term after the Barnett Liberal government suffered a thumping loss in 2017.
"My goals were, after a loss like that, keep the team together, keep the government accountable, highlight as many flaws, and my decision was to review my position halfway through," he told the ABC on Wednesday.
"Well, we're there and I've decided to step down because I'm confident we are in a good position with a number of leadership aspirants and particularly after the federal election."
The federal Liberal-National coalition retained power at the May 18 vote, despite the opinion polls all pointing to a Labor win.
Premier Mark McGowan acknowledged Dr Nahan had taken on a difficult task when no one else wanted the job.
"He had the courage to step up when none of his colleagues would," Mr McGowan said.
"While he has his flaws, like all of us, at least he had the strength to do it, unlike the other contenders."
Dr Nahan said his stepping down was not an acknowledgement he would not win the next state election.
Australian Associated Press
