Winston Peter is the only NZ First candidate capable of winning the Northland by election. If he wins National do not get a top up List MP, so the balance of parliament is altered.
If Winston does win the only major problem for National is RMA reform. National will not have enough votes to push RMA reform through Parliament, just as it didn’t last term. So the smart play from Labour & the Greens is not to run a candidate and let Winston have a chance of winning.
It will be interesting to see if Labour are smart enough to realise this, and the Greens smart enough to realise this is a perfect opportunity to show Winston they can work with him and can be trusted.