The past week has been dominated by opinion polls, and they've certainly been on the minds of the leaders as they travel throughout the country.

Act will be mindful of the fact that it's toppled from a high of 18 per cent in one poll to the TVNZ poll the other night, at just 10 per cent.

What's led to this drop in the opinion of the Act leader, David Seymour, in particular?

In my view, he's become a little too cocky, a bit too big for his boots. What he's saying now is, and has indicated pretty strongly, that if there is a coalition between National and Act, what may happen is that he will give them support on confidence, but not on supply.

That would mean basically an ungovernable government. It's ridiculous, really. David Seymour has backed away a bit and saying he wants a full coalition with the National Party.

But just consider it if there was no support on supply it would mean that National would have to go cap in hand to Act on every piece of legislation.

Now it's different when they're sitting around the Cabinet table because there's collective Cabinet responsibility. That means that any decision that's signed off has the full support of Cabinet.

But in the absence of Act, that'll certainly complicate matters.

I don't think it'll come to that. I think David Seymour has made that pretty clear in subsequent statements he's made. But I think he overplayed his hand and that's why people are looking a bit askance at him and maybe looking towards New Zealand First and Winston Peters.

The polls now are tracking at around 5 percent and for Winston Peters, a month out from the election, a 5 per cent rating is pretty good because it means on election day he'll probably be quite a bit above the 5 per cent threshold.

The bitching between David Seymour and Winston Peters, though, continues with Seymour saying that he wouldn't sit around a Cabinet table with Peters.