The outcome of the seat of Cowper at the Federal Election is expected to be close with the retirement of long serving Nationals member Luke Hartsuyker.
The Nationals hold the seat by a two candidate preferred margin of 8.7 per cent.
It is expected that preferences may influence the outcome due to the possible closeness of the race.
Voters have to number every box to make their vote valid under compulsory preferential voting.
There are eight candidates contesting the seat of Cowper. All were contacted to comment on their plans for preferences for the May 18 election.
Their responses are listed in order of the ballot paper.
Ruth Meads from the Christian Democratic Party has been approached for a comment.
Nationals candidate Pat Conaghan said he was talking to other candidates about preferences.
"I'll always put the voters first if elected, so put me first and vote 1 Pat Conaghan," Mr Conaghan said.
United Australia's Alexander Stewart preferences are as follows 2) CDP, 3) Allan Green Independent, 4) Kellie Pearce Animal Justice, 5) Pat Conaghan Nationals, 6) Andrew Woodward ALP 7) Rob Oakeshott and 8) Lauren Edwards of the Greens.
"United Australia Party has a preference recommendation to put Oakeshott second last because he has not been truly independent," Mr Stewart said.
Labor's Andrew Woodward said they would be advising voters to put the Nationals last, "with good reason".
"The party is still finalising other preference deals," Mr Woodward said.
Independent Mr Oakeshott said he will not be doing any preference deals for the Federal Election.
"I am fully committed to taking an Independent stance to the ballot box and beyond," Mr Oakeshott said.
Greens candidate Lauren Edwards conceded it has been difficult to lock in the Greens preference order.
"As a group we are still in discussion for the final preference order but I can say that our first preference will go to the candidate who most cares about local issues, is determined to prevent climate breakdown and will not sacrifice our forests for a quick buck," she said.
Animal Justice Party candidate Kellie Pearce said she was still in discussions with all candidates to determine who to preference.
However, she said the party would preference those candidates who support the banning of live exports.
"We are wanting to raise awareness of live exports during this campaign," she added.
Independent Allan Green said he will also not be advising voters who to preference.
"I believe the electorate knows what they are doing and I am going to leave it up to them who they preference."