MAYORAL candidate Tim Griffin will lodge a formal complaint to the Electoral Commission Queensland, claiming he was given incorrect voting directions at the Parkhurst Division 1 polling booth.
Margaret Strelow's closest contender said two voting officers told him to "vote one" on the mayoral ballot paper, ignoring optional preference voting during Saturday's council election.
Division 1 was the only division Mr Griffin beat Ms Strelow on primary votes.
Mr Griffin estimated 5000 voters went through the Parkhurst booth and if everyone was given the incorrect instructions it could cost him the election.
But he said his main worry was the misinformation had taken away the democratic right of voters.
Ms Strelow received the second-highest number of votes in Division 1, followed by Lea Taylor, who shared voting preferences with Mr Griffin.
Mr Griffin said his complaint could force a return to the polls for Division 1, or the entire region.
ECQ confirmed Mr Griffin's right to lodge a dispute, but would not comment further so as to remain unbiased.