A record number of candidates running in the by-election will see a surge in informal votes, the Australian Electoral Commission has warned.
This year 17 candidates are vying for the seat of New England, a significant rise to the 10 than ran last year.
A spokesperson for the AEC said voters would be less likely to number every candidate when more are on the list.
“Analysis of past informal ballot paper studies indicates that a higher number of candidates is likely to increase the number of ballot papers ruled informal,” the spokesperson said.
The rate of informal ballots in the seat of New England at the 2016 federal election was 7.04 per cent, compared to a national average of 5.05 per cent.
“People need to number every box on the ballot paper in order for their vote to count,” the spokesperson said.
Early voting opens in Glen Innes, Inverell, Tenterfield and Scone this week – and with just four days left until the December 2 by-election candidates are busy making ground across the electorate.
Punters have Mr Joyce as the favourite on Sportsbet at $1.05.
Independent Rob Taber is running second on $8 while Mr Ewings is paying $34.
CountryMinded’s Pete Mailer said he was “surprised” to be sitting third on $15.
“It’s been very tough to juggle the farm and campaigning but I have a team of people helping,” he said.
Around 110,000 people are enrolled in the electorate and more than 5,000 have already cast their vote.
Pre-polling opens at Tenterfield Memorial Hall at 8:30am on Wednesday and continues until Friday.