Labor and the unions are being accused of playing dirty in the campaign for the southwest Sydney seat of Macarthur.
Liberal member Pat Farmer says his house has been vandalised and campaign posters and an advertising balloon have been destroyed.
He believes the people responsible were bussed in from outside the area.
Mr Farmer has told 2GB’s Alan Jones that suspicion is based on the unexpected arrival of some visitors during one of his regular public forums.
“I had a double-decker brand-new Mercedes bus pull-up beside us,” he said.
“This thing was painted in orange and black writing [anti] WorkChoices – it must have cost them a fortune.”