Winston Peters' attack on Jacinda Ardern's tax vagueness is one of the election's biggest power plays as it shows the kingmaker giving real credibility to a Labour-led Government.
It is actually more of an attack on National than on Labour.
I follow an old rule with Peters: if he is attacking one side, he is actually trying to get votes off the other.
- Winston Peters wants Labour to reveal tax plans
- Labour widens lead over National in new poll
- Winston Peters promises a next-gen Gold Card
So in this case he is attacking Labour - but he is after National's votes.
He is setting himself up as an "insurance policy" for voters worried about what a Labour-led Government will do with its mysterious tax working group.
He has seen Labour's biggest weak link and decided to fill the gap.
The message from Peters is: "vote for me and I will guard against Labour tax excesses".
But the true underlying message here is that Peters thinks Labour can win - and he has decided to get in on it.
Patrick Gower is Newshub's political editor.