Experts say One Nation preferences could have a deciding impact on the outcome of a crucial by-election this weekend.

The dual citizenship fiasco is forcing voters back to the polls in five seats across the country.

A News Corp poll shows federal Labor risks losing the crucial Queensland seat of Longman after One Nation decided to preference the Coalition.

The Opposition narrowly snared the seat at the 2016 election with the help of preferences from Pauline Hanson.

The loss would be humiliating for Labor Leader Bill Shorten, as a government hasn’t won an Opposition seat at a by-election in 100 years.

Galaxy Research Managing Director David Briggs tells Alan Jones it’ll be a close contest.

“In the Queensland state election, only 35 per cent of One Nation preferences flowed to Labor.

“So if a similar result was observed on Saturday then Longman, in all probability, would fall to the LNP.”

What’s worse for Bill Shorten is the poll suggests the seat would be a comfortable Labor victory if Anthony Albanese was Opposition leader.

“We found there was about a 3 per cent increase in Labor two-party preferred and so it took them to 53-47.

“And at that sort of state, you’d be saying that they would be an easy win or not… I don’t know.”

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