GOUGH Whitlam's former seat of Werriwa has been faithful to Labor since the 1930s.
But experts believe it could now be flirting with the Liberal Party.
University of Western Sydney senior politics and history lecturer David Burchell said Labor's federal budget last week aimed to please voters in Werriwa, and seats like it.
"They were trying to deliver an economically credible outcome in a way that sends signals to the heartland that they haven't forgotten them," he told the Advertiser.
"Artfully or accidentally they've managed to deliver a budget that is a surplus and doesn't hit families."
The notion of Labor losing a heartland fortress like Werriwa has already been proven possible.
The state seat of Campbelltown fell to the Liberals in the March 2011 state election with a huge swing of about 21 per cent. Werriwa is held by only a 12 per cent margin.
No Liberal candidate has been named yet to take on Werriwa's Labor MP, Laurie Ferguson, but there is growing speculation.
Dr Burchell said recent polls and state results in NSW and Queensland indicated Werriwa — which takes in parts of Campbelltown north of Leumeah Road and Badgally Road — could fall to the Liberals.
"In the current circumstances it's kind of marginal, which is a bizarre thing to say," Dr Burchell said.
"All the predictions at the moment are that Labor is on the biggest hiding of any government in the last century of Australian politics," he said.
"Macarthur is not of interest in terms of swings because it will stay with the Coalition, but Werriwa on the other hand, it's not impossible that it could go."
He said cuts to foreign aid in the budget would probably be disappointing to those living in well-heeled suburbs more than Werriwa residents.
"It almost signals to the heartland that given a choice between socially progressive folks on the north shore and Labor-minded but socially conservative folks in Werriwa, the latter comes first," Dr Burchell said.
Werriwa Labor MP Laurie Ferguson agreed that things weren't looking too good for Labor.
"Over the past year or so, Labor's been going very badly in the polls and you have to be realistic about things — at the moment we'd have trouble holding a lot of those (heartland) seats," Mr Ferguson said.
"If there was an election held now, I think we would hold Werriwa. But there's no way that you would go to the TAB and bet $1000 on it."
He said he was focusing on making himself available for the electorate by holding weekend meetings, being upfront and honest with people and putting out a good newsletter.
Macarthur Liberal MP Russell Matheson said also he now considered Werriwa marginal.