Liberal party members will select a new candidate to run in former attorney general Christian Porter's seat after he announced he wouldn't contest the next election.
The Perth-based seat of Pearce was held by Mr Porter on a 7.5 per cent margin at the last federal election in 2019 but is now considered a much tighter contest after a boundary redistribution.
Labor has preselected City of Wanneroo mayor Tracey Roberts.
Ms Roberts' council colleague Linda Aitken is touted as a potential Liberal candidate, as is former navy officer Miquela Riley.
The election is due to be held by May.
Mr Porter has held the seat since 2013 and the seat has remained in Liberal hands since its inception in 1990.
The former minister said he wouldn't re-contest the seat after being dumped from federal cabinet following him accepting legal fees from a blind trust.
In a lengthy Facebook post, he said he wouldn't be able to give the next three years his all after "experiencing the harshness of modern politics more than most".
Mr Porter sued the ABC after it published a story about allegations an unnamed cabinet minister had raped a now-deceased woman in 1988.
He strenuously denied the allegations after outing himself as the accused minister and has since settled a defamation case against the national broadcaster.
But it was then revealed in September anonymous donors had paid for part of Mr Porter's legal fees.
Mr Porter denied any conflict of interest and said no banned donors contributed money to the fund, but nonetheless tendered his resignation from cabinet rather than publicly reveal the donors.
The party members will make their selection on Monday.
