National MPs have been subject to a mad-dash stumping campaign, as Simon Bridges and Todd Muller each made a desperate pitch for the party's leadership.
The two are in a bitter showdown accelerated by an devastating Newshub-Reid Research poll on Monday.
Mr Muller sent out an email on Wednesday signalling an intent to challenge - after Mr Bridges threw down the gauntlet, promising to put his position to the test.
A 1 News Colmar Brunton poll is expected soon. All eyes will be on the result and how it might impact Friday's face-off.
RNZ deputy political editor Craig McCulloch has the story.