TVNZ's latest Colmar Brunton poll has Labour on 47 per cent, National on 33 per cent - with Labour unable to govern alone.

The Green party is on seven per cent, ACT on eight per cent and NZ First is on one per cent.

TVNZ's poll comes one night after Newshub's latest Reid Research Poll, which had Labour at 50.1 per cent, National on 29.6, the Greens at 6.5 per cent and ACT on 6.3 per cent.

Jacinda Ardern is on 54 per cent for preferred Prime Minister - no change from previous poll. Judith Collins is on 23 per cent, which is up five points.

David Seymour is showing on two and Winston Peters on one.

University of Auckland politics lecuturer Lara Greaves says the big question is, are Labour going to hold on enough to govern alone?

While they're trending down, the trend is down from record highs.

"I think it is ultimately too little too late [for National]. I think Judith Collins has a lot to turn around in a short time period. I think that she knew on becoming leader that that would become a challenge.

"I think that generally the downward trend from Labour is not due to their incompetency or National's competency, it's more a function of the fact that New Zealand has been through this collective trauma of COVID-19 and associated crisis. We know from studies after studies that when there's a crisis in a country, people tend to cling to the incumbent government."

As for New Zealand First - down on one per cent - Greaves says: "I think at this point we probably have to say there's only a very, very slim chance of them coming back ... it's looking rather unlikely."

As for the Greens, Greaves thinks they may be out of the danger zone. They often poll slightly better than their election result.

"They're kind of heading there... for the Greens to be safe they normally have to be a couple of percent up and I guess we will see, especially now, people are settled into the campaign and we will potentially some more votes will come off Labour in the coming weeks."

What will be interested come the election, is that Parliament is likely to be a four-party affair, Greaves says.

"That's going to create an incredibly strange dynamic where Labour has this flank party of the Greens on the left and National having this flanking party on the right of ACT - we're not going to have any centre parties that have that sort of coalition or blackmail potential ... what that's going to do is put a lot of power in ACT or the Green party depending on of course who is governing."

The election will be held on October 17.

-RNZ