Confidence from the MP for Dunedin North that he has the numbers to push legislation through Parliament's first stage that would Monday-ise public holidays.
David Clark wants ANZAC and Waitangi days moved to Monday when they fall on a weekend - something that happens about twice every seven years.
He's released documents which he says show officials are "cherry picking" the costs of the plan.
Mr Clark has the support of all parties but National and ACT - so he's calling on John Key and his caucus to come out in support of the move.
"What he seems to be doing so far is dog whistling to employers and from what I've heard, most employers are actually in support of the bill so he may yet change his position, ACT is the only party that's come out against it."
He says John Key's quarter of billion dollar estimate of the move looks at costs, but none of the benefits.
"Employers are not subject to the Holidays Act but they are counted in his numbers. There's productivity gains from having properly rested workers and they're not counted, there's also a domestic tourism benefit that we know is estimated at around $35-$40 million."
A government spokesman says the National party caucus hasn't yet discussed the bill.