Sitting Liberal Nicole Flint is hanging onto a slim lead in South Australia's most marginal federal seat but oil exploration in the Great Australian Bight has emerged as a key issue.
In a ReachTEL poll conducted for the Australia Institute, Ms Flint is ahead of Labor 51-49 per cent on a two-party preferred basis.
But the poll also found that about 60 per cent of voters are opposed to oil drilling in the Bight and about 84 per cent supported declaring the area a World Heritage zone.
Australia Institute SA projects manager Noah Schultz-Byard said the poll showed that Boothby was clearly in play at the next election.
"The last time Labor held Boothby was shortly after World War II, way back in 1949, but the Liberal Party's margin has been in decline over recent years," he said.
"Protecting the Great Australian Bight is clearly a big issue for voters in SA and any party wanting to take the seat of Boothby needs to consider where they stand on that."
The ReachTEL poll took responses from more than 700 voters in Boothby, which sits in Adelaide's southern suburbs and covers a large part of the city's coastline.
Ms Flint currently holds the seat with a margin of about 2.8 per cent.
Australian Associated Press