With almost 80 per cent of ballots counted in the race for the inner northern Brisbane seat of Stafford late on Saturday evening, Labor was leading the LNP by 768 votes, according to chief ABC analyst Casey Briggs.
"Labor is likely to retain Stafford," he said.
"There has been a 4.1 per cent swing against Labor with additional postal votes still to be counted," he said.
"But for the LNP to win from here, those postal votes would need to break very strongly in its favour. That is very unlikely to happen."
Neither party was able to make a declaration and with preferences crucial, multiple counts will probably be required to confirm the result.Â
Mr Briggs said postal ballots were the biggest variable remaining as it was uncertain precisely how many would end up being returned and counted.
Polls closed at 6pm, with more than 14,000 people casting ballots on the day.
Almost 42 per cent of electors chose to vote early, 13,530 in person and 3860 by post.
Electoral Commissioner Pat Vidgen said staff were counting first preferences from votes taken on election day, during early voting, telephone voting and the postal votes returned so far.
"Voting finished at 6pm ... but it could still take a few days to determine the results," he said.
"We'll only declare successful candidates when the outcome is certain."
Voters were called to the polls on Saturday in the electorate of Stafford after the sudden death of former independent MP Jimmy Sullivan on April 9.
Mr Sullivan - who had a 6.83 per cent swing against him in the 2024 election - was expelled from the Labor Party in May 2025 over legal and medical concerns.
The seat has been held by Labor for most of its history, with Mr Sullivan's father Terry serving as the member from 2001 to 2006.
Labor's Luke Richmond notionally still holds the seat with a 5.3 per cent two-party preferred margin.
But recent polling suggested the LNP could be on track for an unexpected and historic victory.
Griffith University political scientist Paul Williams predicted that Fiona Hammond would win the seat for the LNP.
With by-election swings towards a sitting government rare, even a reduction in Labor's margin would technically be a loss for Labor and former premier Steven Miles.
And if the seat is lost, it would likely be terminal to his leadership, Prof Williams said.
One Nation did not stand a candidate in the vote.
15°C