One Nation has pulled off an historic byelection victory in the Labor stronghold of Western Australia, claiming the outer suburban seat of Secret Harbour and securing its first lower house seat in the state.

By 10.30pm, with 80 per cent of the vote counted, Herdegen had amassed a primary vote of 39 per cent, ahead of Labor candidate Georgia Tree’s 24.4 per cent and Liberal candidate Ryan Robertson’s 17.3 per cent.

Voters in the safe Labor seat cast their ballots on Saturday after senior minister Paul Papalia’s mid-term retirement triggered the contest.

Declaring victory, One Nation candidate and gym owner Luke Herdegen vowed the party would carry its momentum into the Victorian state election.

Herdegen has been buoyed by a sea of polling booth orange across the beachside state electorate, south of Perth.

WA One Nation candidate for Secret Harbour Luke Herdegen at the Coastal Lakes College Polling Place in Perth. Photo: AAP

“The people of Secret Harbour have sent a message, a message that will send shock waves across the entire country,” Herdegen told supporters.

“None of these MPs are safe from the orange tsunami.”

While Labor was yet to concede, WA Premier Roger Cook said it would be a battle to hold the outer-suburban mortgage-belt electorate despite Labor’s 11.5 per cent margin.

“It would break my heart,” he said when asked about defeat.

“Byelections bring up all kinds of opportunities for a whole range of issues to impact on the seat.”

WA Labor candidate for Secret Harbour, Georgia Tree, with WA Premier Roger Cook at the Secret Harbour Primary School Polling Station in Perth. Photo: AAP

On the ground in Secret Harbour, Labor is on the nose, with cost-of-living pressures, housing and a perceived lack of community amenities topping lists of voter concerns.

Local Luke Pors voted for One Nation and believes it will do a better job than either Labor or Liberal.

“We know what their true goal is and I think just in One Nation we trust,” he said.

The Qantas flight attendant was also impressed by Herdegen’s campaign.

“He’s like a home buddy and as obviously a youngie; we can really connect with him,” he said.

Retirees Ann and Les Scard also voted One Nation.

“It has been a pretty strong campaign by Luke Herdegen,” Les Scard said.

“He deserves a chance.

“I get the impression Liberal and Labor are desperate; they’re doing everything to try and discredit them and I don’t think they’re being successful.”

Ann Scard isn’t concerned by One Nation’s controversial immigration policy.

“I agree with a lot of what Pauline Hanson says,” she said.

“Something has to be done, it’s just all askew.”

Herdegen believes people are desperate for change.

“They’re struggling with cost of living; there’s a major housing issue here with the mass immigration coming through and people have just had enough,” he said.

Retired truck driver Dean Maxwell isn’t so sure. He voted Labor.

“I didn’t vote for One Nation, I put them last,” he said.

“I just don’t see any good policy.

“I don’t like any of the pollies but I particularly don’t like Pauline Hanson.

“I think she’s in Gina Rinehart’s pocket.”

Labor candidate Georgia Tree said she would fight until the polls closed but admitted protest votes against the status quo could hurt her prospects.

“It’s been an absolute rollercoaster,” she said.

One Nation’s performance in the tradie haven will be of interest across the nation, particularly Victoria, which has a state election in November.

-with AAP