National goes into the last week with enough support to govern with just ACT's David Seymour and Peter Dunne of United Future. Its latest four-poll rolling average, including the unpublished UMR poll in early September, was 47.1%. (Polling finished on 10 September.)
Even if National drops 1.5%, two seats for the Maori Party would be enough to keep it in power without needing Winston Peters' New Zealand First or Colin Craig's Conservatives.
National's trend from mid-June to early September was a fall of around 3.5% to around 47.8% (a bit above its actual reading). But it is too early to draw conclusions about the election outcome from the trend. There may be last-minute upsets. Kim Dotcom has been trying to generate one.
The Greens continued to hold up strongly, at 12.8%. The party's trendline points toward roughly that outcome on Saturday. Labour continued to languish, at 25.2%. Its trend has been down slightly but it appears to have troughed around that figure.
National's lead over Labour and the Greens was still a very lengthy 9.1%.
New Zealand First looks set to clear the 5% target easily, with an average of 7.1%. The Conservatives were still short at 4.1% but continuing to rise. Internet-Mana has slumped to 1.7% ahead, the Maori Party was 1.0%, ACT was 0.6% and United Future 0.1%.
And here is how the latest poll average would translate into seats, assuming David Seymour wins Epsom and Peter Dunne wins Ohariu - and also assuming both parties get at least 0.4% in the election. If not, they would be "overhangs" and push up the number of seats in Parliament by two, requiring 62 for a majority. The table also assumes the Maori Party wins Waiariki and one of Te Tai Hauauru or Tamaki Makaurau, which recent polls have split near evenly between the Maori party and Labour. That additional seat is an "overhang".
|Parties||Latest 4-poll average||Seats|
|National side (total)||61|
|Could go either way||11|
|New Zealand First||7.1%||9|
|Labour-Green side (total)||47|
|Total seats including overhangs||121|
* ACT and United Future are both assumed to get above 0.4% in the actual election and so each earn a party vote quota. They would then between them add only one net seat to National's side because National, having half the total party votes, would lose one quota. This is dealt with in the table by subtracting one seat from National to give it 59.
** The Maori Party is assumed to win Waiariki and one of Te Tai Hauauru or Tamaki Makaurau, which would be one more electorate seat than the total its 1.1% party vote entitles it to. That would therefore be an overhang seat, pushing the total seats up to 121.
The poll of polls is an arithmetical average of the four most recent major polls since mid-June from among: TV1 Colmar Brunton, TV3 Reid Research, Fairfax Media-Ipsos, NZ Herald DigiPoll, Roy Morgan New Zealand and UMR Research, which is not published. The four polls included in the latest average were, in date order of the midpoint between the start and finish of voter interviews, TV3, UMR, NZ Herald and TV1. The TV1 midpoint was 8 September.