KEY POINTS:
Winston Peters' travails are taking their toll in the polls. From a high point of 4 per cent and heading up in mid-July in the "Poll of Polls" rolling average, his NZ First party sank to 2.7 and heading down in late August (chart 1) - just half the 5 per cent it needs for seats in the next Parliament.
Contrast that with 8 per cent and falling at a similar time before the 2005 election - from which NZ First scratched just 5.7 per cent.
The rejection by National leader John Key of Peters as a potential minister removes a possible source of rescue. In 2002, NZ First benefited from National sympathisers jumping its leaking ship to a party which might be a brake on Labour in power. The same might have happened in reverse if Labour's ship is leaking badly close to this election. But, now that NZ First cannot exert leverage over National, that is less likely. There is a spring lift for Labour. Its latest average is 36 per cent, up from a trough of 30 in mid-June. But it still languishes far behind National, on 51 per cent (down from a peak of 55 per cent in mid-June).
There is another issue for Labour: that its recent rise has been to the Greens' cost - the Greens have dropped to 4.7 per cent. That has led some to ponder a nasty paradox for Labour: it needs the Greens for any hope of putting together a fourth-term combination; but to get the votes it needs to be in the game, Labour may push the Greens below 5 per cent.
In fact, while over the past month or so there has been a mirror image (chart 2), until then Greens support this year was fairly stable while Labour bounced around. So it is not impossible Labour could go up and the Greens get back over 5 per cent.
* The Poll of Polls is a rolling average of the four most recent polls at each point. Since five polls are included, one is necessarily missing from each point and sometimes a poll will feature twice. The five are Herald-DigiPoll, TV One-Colmar Brunton, TV3 TNS, Fairfax Neilson and Roy Morgan (once a month). UMR, included in earlier data, has withheld data since April.
