Australia's opposition party claimed victory in a special election for a district in Queensland previously held by Kevin Rudd, Prime Minister Tony Abbott's defeated opponent.
Labor's Terri Butler, an employment lawyer, thanked voters on her Facebook page for her victory, even as the Liberal-National government refused to concede. With postal votes yet to be counted, Labor has 52.3 per cent of the vote, according to the Australian Electoral Commission's website. Liberal-National candidate Bill Glasson has 47.7 per cent.
A Labor victory in the inner-city Brisbane seat of Griffith is "the most likely outcome", George Brandis, the government's attorney general and a Queensland senator, said. Still, he said, "it's too early to declare victory or concede defeat".
Abbott's coalition has trailed in opinion polls since winning power in September, its popularity dented by domestic issues.
In Griffith, Labor leads the Liberal-National coalition by 3,148 votes, the Australian Electoral Commission website showed. Brandis said there were more than 10,000 postal and pre-ballot votes that needed to be counted.
A Labor victory would see the party maintain its 55 seats in the lower house of parliament, compared with the coalition's 90.