Debate features Green Party leader James Shaw, Act Party leader David Seymour, Maori Party co-leader Marama Fox and newly-appointed United Future leader Damian Light.
The minor party leaders will get their time in the spotlight this evening, but there will be one key person missing.
NZ First leader Winston Peters has opted out of TVNZ's Multi Party Leader's Debate, saying there is no point taking part if National and Labour are not there.
It will feature Green Party leader James Shaw, Maori Party co-leader Marama Fox, Act Party leader David Seymour and newly-appointed United Future leader Damian Light.
Despite polling higher than three of the parties in the debate, The Opportunities Party leader Gareth Morgan will not be there.
Morgan made an unsuccessful court challenge against TVNZ over its rules for inclusion, which require parties to be represented in Parliament or be polling at higher than 3 per cent.
Top has been polling at between 1 and 2 per cent.
The debate is a rare opportunity for the minor party leaders to get national airtime. They have mostly been drowned out by the two-horse race between Labour and National.
As a result, the Greens and NZ First have fallen in popularity.
A 1News-Colmar Brunton poll released last night had the Greens on 5 per cent - down 6 points from a month ago. NZ First were on 9 per cent, down 2 points on last month.
That means there is all to play for. The Greens need to lift their vote to be sure of re-election. NZ First needs to ensure it remains in the kingmaker position.
The debate, which starts at 7pm, will be hosted by TVNZ political editor Corin Dann, who stepped in after Mike Hosking pulled out because of illness.
Andrew Bydder was found to have breached code of conduct but won't apologise.