Tim Watkin has a sneer at the ACT Party and makes this observation:
Key will also be looking intently at the polls. The worst outcome for him is that he has the cup of tea, only for Banks to lose the seat thanks to those utterly turned off by ACT and Labour supporters voting for National.
The worst outcome for Key is pretty bad. Say he has his cup of tea with Banks, sending a signal that National backs ACT in Epsom, and far-right voters around the country decide this means a vote for ACT is not a wasted vote, and ACT surges up to, say, 3.5% almost all of which comes from National. And THEN the voters of Epsom fail to give their electorate to Banks out of sheer bloodymindedness. The wasted ACT vote means National drops down to ~49% and Key needs Dunne, Turia and Sharples to form a government.