The Liberals have chosen pastoralist Will Baston to contest the seat of North West Central following the retirement of sitting Nationals MP Vince Catania.
Pub owner Merome Beard is running for the Nationals, who retained the state's largest electorate by just 259 votes at last year's election.
Labor ran a close second after securing an 8.4 per cent swing but is yet to confirm whether it will run a candidate this time around, having already secured unprecedented dominance with 53 out of 59 lower house seats.
The Nationals are comfortable favourites to retain the seat should it remain a two-horse race.
Mr Baston, 36, runs his family's Jimba Jimba station on the Gascoyne River and is also a qualified urban and regional planner.
He is promising to fight for better regional health services and local community engagement to reduce youth crime.
"The rising cost of living is hurting locals who must travel over large areas to get access to basic essential services, such as maternity service," Mr Baston said on Wednesday.
"Local mothers should be able to have their baby in Carnarvon rather than having to go to Geraldton or Perth."
The WA Liberals were reduced to just two lower house MPs at last year's election amid internal turmoil over alleged branch-stacking and the influence of factions.
Their dismal performance allowed the Mia Davies-led Nationals to formally claim opposition status, relegating the Liberals to junior alliance partners.
Ms Beard, 55, is a well-known Carnarvon local and former world championship rower with experience in hospitality, tourism and finance.
"The Nationals seek out local champions that have committed their lives to improving outcomes for regional communities, and Mem fits the bill perfectly," Ms Davies said last month.
"She has extensive experience as a small business owner in the hospitality sector, links to the pastoral industry and has been involved with numerous community organisations."
Mr Catania, a former Labor MP who defected to the Nationals in 2009, will formally step down in August.
He said last month he had "nothing left in the tank" and wanted more time with his wife and five teenage children.
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