New Zealand First leader Winston Peters says there is no place for backroom dealing in the by-election for the Northland electorate.
National, Labour and Act have all put candidates forward after the sudden resignation in January of Mike Sabin, who had held the seat for National since 2011.
Mr Peters said his party would not engage in cross-party deals such as partnering with Labour to avoid splitting the centre-left vote.
"What other political parties do is part of their political and democratic process.
"We have never done deals. And we are campaigning for every vote from wherever that vote may come from, because we need a cataclysmic change here."
Mr Peters said voters needed to focus on the issues and not on political dealings.