The Dunkley byelection is a must-win contest for both the Labor government and the Liberal opposition.

Both Anthony Albanese and Peter Dutton face the grim reality of being politically diminished if voters reject their candidates on Saturday.

For the Albanese government, losing the seat would trim an already thin buffer to a three-seat majority ahead of a 2024 federal election, and risk a further slide in popularity.

The Labor Party is leaning on the legacy of well-liked former member Peta Murphy, whose death after a long battle with breast cancer triggered the by-election, by choosing her political protégé Jodie Belyea.

Across the aisle, failure will pose serious questions about Dutton’s appeal in the type of electorate his party must win if it wants to return to government.

Dutton — buoyed by the successful ‘No’ campaign against a Voice to Parliament — declared the byelection as “an opportunity for Australians to send a message.”

A Liberal member represented Dunkley from 1996 to 2019, but since losing the seat to Murphy the party’s presence in suburban Melbourne has all but disappeared.

A bruising defeat in the eastern-suburbs seat of Aston last year — long considered un-winnable by the Labor Party — was the first time the government had won a seat from the opposition in a byelection since 1920.

The Liberal party has seemingly learnt from its mistakes in Aston, where it parachuted a Brunswick-based captain’s pick, by allowing the pre-selection by members of Frankston mayor Nathan Conroy.

The candidates

Both Labor’s Belyea and the Liberal’s pick Conroy are well-known locally.

Belyea, a Frankston local, said Murphy inspired her to join the Labor Party and politics.

“Peta and I shared similar values: compassion, fairness and a deep commitment to social justice,” she said in a statement.

“These shared values are how we first met – through my work with the Women’s Spirit Project – a community organisation supporting women doing it tough, that I founded in 2018.”

Jode Belyea said former member Peta Murphy inspired her to enter politics. Photo: AAP

31-year-old Conroy, an Irish immigrant, is serving his third consecutive term as Frankston mayor.

The Liberal Party has bolstered Conroy with a $900 million pledge for a rail line extension in Frankston, while also making a financial commitment for a Carrum Downs sporting reserve.

The Liberal Party pre-selected popular Frankston mayor Nathan Conroy. Photo: Nathan Conroy

He was contacted for comment.

Six other candidates have declared for the byelection, including Greens candidate Alex Breskin and representatives from the Animal Justice Party, Victorian Socialists and the Australian Democrats.

Battle lines

The Labor Party has pushed the reworked stage three tax cuts as a cost of living measure, which Belyea said was the number one issue raised while door-knocking.

Polling from the Australia Institute found that 66 per cent of Dunkley residents backed the changes, based on a survey of 626 residents.

According to the Australia Institute, around 24,691 — or 30 per cent of the electorate — will now receive a tax cut.

The Liberal Party, cornered into passing the stage-three tax cuts, has instead attacked Albanese’s brand and argued it is a referendum on a “bad government.”

While polling has Labor ahead by a slimmer margin than in 2022, where Murphy retained the seat 56.27 to 43.73 per cent, a loss for either party will send a message that its leaders cannot ignore.