The Miles government appears certain to have lost the safe seat of Ipswich West after an 18 per cent swing gave Ipswich Show Society president Darren Zanow and the Liberal National Party a 2.9 per cent margin.
The LNP also cannoned through a 28 per cent margin former premier Annastacia Palaszczuk built up in Inala before retiring in 2023.
Labor's primary vote fell to a historic low of 36 per cent but projections on Sunday had candidate Margie Nightingale retaining the seat in Brisbane's southwest on a seven per cent margin, beating out the LNP's Trang Yen.
Labor's Margie Nightingale was supported by Premier Steven Miles in her bid for the seat of Inala. (Jono Searle/AAP PHOTOS)
Federal Nationals leader and outback Queenslander David Littleproud said everyone in federal and state Labor should be very concerned about the results.
"This is a big 'up yours' to the Queensland Labor government,' he told Nine's Today on Sunday.
"But I wouldn't be measuring up the curtains just yet.
"If I was (LNP leader) David Crisafulli, there's a lot of work to do between now and October."
The Queensland election is due to be held in October, with an opinion poll released on Friday indicating Mr Miles is facing defeat.
The premier's rivals, the LNP, led the two-party preferred vote 54 per cent to 46 per cent in the poll published by News Corp.
Today Queenslanders in Ipswich West and Inala were asked to send Labor a message.— David Crisafulli (@DavidCrisafulli) They've done just that.March 16, 2024
The pain continued for Labor in the Brisbane City Council elections, suffering a 5.5 per cent fall in primary votes as 800,000 electors kept the LNP in power at City Hall.
Federal Aged Care Minister Anika Wells, whose electorate of Lilley is in northern Brisbane, said there was "clearly a lot for us to work on" but she was closely watching the council results in her electorate.
"There are two races ... currently are on a knife's edge where we - Labor - are genuine prospect of taking two wards off the Liberals at Brisbane City Council which remains the largest Liberal government on the mainland for Australia," she told Sky News on Sunday.
Mr Miles told reporters on Saturday he expected swings against the government "in the double digits" but underlined swings against governments were expected.
Since 1992, the average swing against Labor at by-elections when they are in government is five per cent.
About a third of voters had already made up their minds and submitted their decision before election day across both seats, according to the Queensland Electoral Commission.
Contested for the first time in 1992, the Inala electorate was initially represented by Ms Palaszczuk's father Henry.
He went on to become a senior minister before being succeeded by his daughter who resigned in December.
Inala is considered Queensland's safest Labor seat but Ms Palaszczuk took no chances on Saturday, stopping by a polling booth in the electorate to show her support.
Until Saturday, Labor had only once needed preferences to win the seat, winning more than 50 per cent of primary votes at all but the 2012 election when Ms Palaszczuk won 46 per cent.
Her replacement, Ms Nightingale, appears to have won about 36.5 per cent of primary votes.
The Ipswich West by-election was triggered by Labor MP Jim Madden leaving in January.
He will run for Ipswich council election in Saturday's Queensland local government elections.
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