Abbott supporter assaulted with corkscrew

An irate man has assaulted a Liberal volunteer with a corkscrew at a polling station in Tony Abbott's Sydney electorate on the eve of the federal election.

The 62-year-old man allegedly began yelling abuse at volunteers who were putting up campaign material outside the Balgowlah Heights Public School just after 8pm on Friday.

Police said the man allegedly threatened an 18-year-old man before thrusting a corkscrew at a 31-year-old volunteer's stomach, causing a minor injury. He then started tearing down the banners before fleeing.

The victim was treated by paramedics and didn't need to go to hospital. The alleged attacker was arrested at Balgowlah Heights about 10.30pm and taken to Manly Police Station, where he was charged with two counts of common assault.

The man is due to face the Manly Local Court on June 5.

The contest for Warringah has seen some of the dirtiest tricks of the campaign, including a book with faeces inside being dumped outside Mr Abbott's Manly office.

Former Olympic skier Zali Steggall is vying to wrestle the seat from Mr Abbott, who has held it for 25 years.

On the eve of Saturday's election the former prime minister was widely criticised for suggesting the late Bob Hawke had a "Liberal head".