Voters are determining the fate of Turnbull government as well as their local representative in a traditionally Liberal seat

Polling booths have opened in the Bennelong byelection with Kristina Keneally fighting an uphill battle to overturn a 9.7% Liberal margin. Polls suggest the Liberal John Alexander is the favourite, but the seat is very much still in play.

The prime minister, Malcolm Turnbull, acknowledged it was a “very, very close contest” when he and Alexander met voters at Gladesville Public School on Saturday morning.



“Australia’s security and prosperity depends on John Alexander being back part of our government, delivering more than 1000 jobs a day,” Turnbull said.



Keneally declared she was feeling “energised” by the campaign before handing out how-to-vote cards at Ryde East Public School. “There has never been a more important vote in Bennelong,” she told reporters.

“Indeed the people of Australia are looking around at Bennelong, looking at this seat and wishing they were having their chance to have a say on this government.”

Bennelong has historically favoured the Liberals. Labor famously won the seat from John Howard in 2007, but it has otherwise elected Liberals at every election since its creation in 1949.

During Howard’s time, the seat shifted west, away from the north shore, and the area became much more diverse. The seat became more marginal, but it still definitely leans to the Liberals.

The 2001 census recorded that 10% of the seat’s population was born in China, Hong Kong or South Korea – that number had grown to 20.8% in the 2016 census. Bennelong is ranked 13th out of 150 electorates in terms of the proportion of the population who don’t speak English at home.

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Alexander won a third term in 2016 with a 9.7% margin. National polls suggest a national swing to Labor of up to 5%, but byelections often see larger swings. A 10% swing is definitely achievable.

There have been four polls in Bennelong – two gave Alexander a lead of 3%, while the other two had the race tied. Seat polling is not a perfect science, but these polls suggest a sizeable swing to Labor. Trying to make a more precise prediction risks leaving egg on your face.

Twelve candidates are running – a large field but not that unusual for a prominent federal byelection. In addition to Keneally and Alexander, there should be a significant vote for the Greens, and possibly for Cory Bernardi’s new Australian Conservatives party, who are competing with the Christian Democratic Party on the right. Greens preferences should favour Labor, while you would expect the Conservatives and the CDP to favour the Liberal.

The electorate is centred on the Ryde council area and Epping, north of the Parramatta river. The Liberal vote is highest in areas such as Putney, Eastwood and Epping. The western end of the electorate, including Eastwood and Epping, tends to be more multicultural, while the suburbs closer to the north shore are less so.

There has been a great deal of speculation about whether these multicultural communities, particularly those of Chinese and Korean backgrounds, may abandon the Liberals. The government may have lost support with its citizenship legislation, and more recently its loud attacks on Labor and Sam Dastyari for his links to Chinese donors.

But it would be foolish to assume these communities are monolithic and will all vote the same way. Larger swings in the multicultural western end of the seat could indicate that parts of the Chinese and Korean communities have moved away from the Liberals.

This byelection will play a big role in either solidifying or destabilising the Turnbull government – a win restores its majority, while a loss will leave it relying on the crossbench for support.

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This will be a factor for the voters – they are not simply choosing a local representative, but also determining the fate of a government. Will it govern with a majority, or limp along until the next election?

There is no particular reason to think people are more likely to vote Labor due to Alexander’s citizenship troubles. Past byelections triggered by section 44 eligibility problems have generally resulted in the ousted member being returned, usually with an increased vote.

But voters clearly have other reasons to consider switching to Labor – national polling has put Labor in a clear lead in almost every poll since the last election, and electing a Labor MP in this traditional Liberal seat would send a very clear signal that this government is probably nearing its end.