New Zealand First leader Winston Peters is fond of Kenny Rogers' advice in The Gambler: "You've got to know when to hold 'em, when to fold 'em, know when to walk away and know when to run."
National Party leader Simon Bridges is around the poker table and has calculated that Winston Peters is bluffing about his hand - and so he is holding.
Bridges' unequivocal decision to rule out any deal with NZ First after the election is a gamble.
But it is a calculated one.
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Bridges has worked out he has more to lose from keeping Peters on National's radar than he does from ruling him out.
Bridges is betting Peters would always have sided with Labour if he was the kingmaker in 2020 anyway. In all likelihood, the bulk of National Party voters too will have worked that out themselves.
But there will also be a few who might think they are being clever and vote strategically for NZ First. Bridges is betting the election will come down to a very narrow margin.
He wants every single vote he can get - and that means spelling it out to National Party voters that there is absolutely no hope of a National-NZ First Government.
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It is a big risk because in the event Peters is again the kingmaker, people will conveniently forget they thought he was always going to go with Labour anyway.
Bridges will cop the flak for National not getting a chance. But if Peters is out of Parliament altogether, Bridges will be praised for his canny decision.
And that is Bridges' overall plan - cutting off enough voters so NZ First falls short of the 5 per cent threshold to get back in.
Hence the reason he cited for the decision was a lack of trust in NZ First. The specific reason was the court case against National MPs while he was negotiating with them.
Trust was the same reason former PM John Key cited in 2008 and 2011. Bridges is hoping for the same result as 2008, when NZ First ended up out of Parliament.
Peters inevitably decried Bridges' decision, saying that if Bridges wouldn't pick up the phone somebody else in National would.
But it blunts his usual campaign tool of saying NZ First could go either way.
It means Peters' only remaining tool is to argue that only a vote for NZ First can stop a Labour-Greens Government.
That argument alone may be enough for some National voters to tick the black and white box.
But that will only be effective if polling shows Labour and the Greens have a high chance of making it alone.
If the battle is close, National voters will hunker behind National to try to get them over the line.
It is likely there is some trepidation in the caucus about the move.
But as they headed into the caucus meeting at Havelock North on Sunday, National Party MPs were asked to describe Peters in one word.
Judith Collins settled for "still alive". Northland MP Matt King chose "crafty". Others used mercurial, wily, and "done his dash".
Dan Bidois was the bravest: His word was "gone".
On election day the chips will get counted and either Bridges or Peters will take the lot. The other will be running.