One Nation's Luke Herdegen has declared Perth's south as the party's "heartland'" after a significant Secret Harbour by-election victory.
Herdegen secured One Nation's first Lower House seat in state history at the weekend, with 57 per cent of the votes after preferences, ahead of Labor's Georgia Tree with 43 per cent.
Speaking outside of his soon-to-be electorate office in Secret Harbour on Sunday, Mr Hedergen said there are no safe Labor seats in Perth's south anymore.
"Kwinana, Baldivis and Rockingham...they are ripe for the taking. This is One Nation heartland now," he said.
Despite the rivalry, Mr Hedergen acknowledged Ms Tree's efforts in her campaign and urged his supporters to show her "some love".
"This is certainly not a loss for Georgia Tree...this is a loss for WA Labor," he said.
“I think Georgia Tree is an honest, hardworking person, I was lucky enough to spend some time with her father on the booths as well and he is a really great guy.
“Anyone who’s supportive of me show George some love.”
Ms Tree said it had been an honour to fight for her community.
“Congratulations to Luke Herdegen. It is a great honour to represent your community in parliament – and it is a massive responsibility," she said.
“While the result wasn’t what we hoped for, I am incredibly proud of what we achieved."
One Nation Leader Pauline Hanson said they would continue to target Labor-held seats.
“The result in Secret Harbour should be a warning to Labor, we’re coming for more of your seats,” Hanson said on X.
“Australians are choosing One Nation as a serious alternative to the tired old uni-party who have destroyed our nations economic prowess.”
The Secret Harbour by-election was triggered by the resignation of long-serving Labor MP Paul Papalia.
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