David Crisafulli is at risk of squandering an overwhelming mandate in the Queensland parliament after the buttoned-down opposition leader was given a lesson in dealing with election campaign pressure by a freewheeling Labor rival with almost nothing to lose.

Mr Crisafulli’s Liberal National Party is still on track to end nearly a decade of Labor rule in Australia’s third most populous state on Saturday, but internal and public polling suggests the threat of 20-seat wipeout for Labor that was real just weeks ago has receded.