National Party leader Simon Bridges is expected to face a no-confidence vote when his caucus meets next Tuesday unless a second poll shows a change in fortune for his party.
Several senior MPs have told the Herald they are now expecting a vote on Bridges' leadership after a dire Newshub Reid Research poll put the party on just 30.6 per cent.
It is understood Bridges has been told to expect that vote, but has so far shown no inclination to stand down over his own accord, saying public opinion will shift as the election nears.
Some MPs doubted Bridges still had enough support to win a confidence vote barring a miracle between now and Tuesday. If he loses that vote, it will spark a leadership contest.
That miracle could come in the form of a 1 News Colmar Brunton poll due out on Thursday.
If it shows public opinion is starting to shift back in National's favour it could yet save Bridges given a lack of appetite among some MPs for a messy leadership change.
National's internal polls are due on Wednesday and could also be critical.
As yet there is no clear majority behind any of the potential contenders for his job: Todd Muller, Mark Mitchell, Judith Collins or potentially Paula Bennett.
It remains unclear who would put up the no-confidence vote: neither Todd Muller nor Mark Mitchell will have any appetite for such a direct challenge of Bridges.
Judith Collins has more guts than that, but the most likely option is an MP who is outside the direct circles of the main contenders.
The looming caucus meeting will be preceded by a week in which Bridges is prevailed upon to stand down to allow a seamless change rather than a messy scrap.
It will also start the race to 28: the number of MPs that one candidate needs to win a new leadership contest.
By next Tuesday, MPs will have had a week away from Parliament with party members and members of the public getting in their ear about the leadership.
The dream scenario would be for Bridges to step down and caucus to anoint another quickly without a contest.
The first appears unlikely unless Bridges' own bedrock supporters went to him to say it was time to go.
That would be the likes of Paula Bennett, Paul Goldsmith, Todd McClay and Michael Woodhouse.
Bennett has been akin to a mother bear in her loyalty to Bridges so far – but Bennett is also the campaign chair and so has to put loyalty to the party ahead of loyalty to any one person.
The only other way to avoid a contest is for one person to present a win as a done deal: one person sews up majority support ahead of that caucus meeting and forces Bridges hand as well as closing out other contenders.
The trouble is that more than one person thinks they should be anointed: Todd Muller, Mark Mitchell, and Judith Collins. Paula Bennett's name could also appear in the mix.
Muller and Mitchell have both publicly expressed support for Bridges since the poll.
Muller said "no" when asked about leadership ambitions by The Country on Tuesday, saying Bridges was "doing a bloody tough job well" and that nobody could predict now that National could not win the election.
"I do not believe we can sit here now, 130 days out from an election when we are about to tip into the greatest recession of a generation, that you can make that view that National cannot win.
"I don't believe it, I know the National Party caucus don't believe it, and I know Simon doesn't believe it."
But the potential contenders – including Muller - will be conducting manoeuvres to shore up their numbers and outflank their rivals, either in preparation for Bridges to stand down or if he loses that confidence vote.
Those who are not yet actively courting support are nonetheless letting MPs know they intend to contest it to ensure potential supporters do not side with a rival.
But the caucus is split especially the liberal wing such as Nikki Kaye, Nicola Willis, and Chris Bishop who back Muller – and the Christian conservatives who are more likely to back Bridges or Collins.
That could leave room for Mitchell or Bennett to claim it through the middle.
If nobody can reach that mark by Tuesday, it is likely National will wait a further week to elect a new leader rather than run the vote then and there.
MPs told the Herald that despite the undesirability of dragging out the matter, natural justice had to apply and the contenders needed to be given time.
Securing support is also a game of negotiations.
So there may be promises of particular positions in return for support, although that can be dangerous.
One of the reasons Jami-Lee Ross claimed to have soured against Bridges was because Bridges had promised him the role of Chief Whip, only to give it to another. That did not turn out well for Bridges.
Those negotiations may include Bridges himself if he decided to stay on: a deal in which Bridges offered his support in return for a good position, such as finance.
Bridges is likely to put up a fight to try to turn his fate around.
He will be dedicating his energies to persuading MPs of two things: that without a 'Jacinda' figure a leadership change will do more harm than good, and that the public mood will shift back in National's favour once the economic hit starts focusing voters' minds.
He will be highlighting the polling after the Christchurch mosque attacks that showed public sentiment can turn on a dime.
However, a number of MPs have told the Herald that Bridges' performance is constantly raised with them when they are out and about – and not in a good way.
Ask any Labour MP, and they will tell you it was the same when David Cunliffe led their party.
Ominously, National MPs have started talking about the 'Bridges effect' and trying to calculate how much of a factor Bridges will be on the party's chances. One estimated he was costing at least five percentage points in the polls.
That tends to make electorate MPs campaign on their own credentials rather than the party's – and that is detrimental to the party's overall vote.
While many believe National's polling will indeed rally, the question is whether it will rally more under another leader.
That in the end will be what sways them.
National MPs have held their nerve before, and it has paid off: after Jami Lee Ross' dramatic exit, and after the Christchurch mosque attacks when National's polling dipped and Labour's rose, only to come around again.
But asking them to bottle their nerves again four months before an election with no sign of the PM's popularity waning any time soon may prove too much.