The political commentariat was at its most skittish following the release of two public opinion polls last Monday.

The Taxpayers Union/Curia poll released in the morning projected a hung Parliament, with neither the centre-right nor the centre-left blocs able to claim a majority. That prospect excited much idle speculation for most of the day about what that eventuality could mean.

However, that evening’s TVOne/Varian poll showed the coalition government being re-elected with a reduced majority, despite the falling popularity of the Prime Minister. That immediately set off a round of comment about how long the Prime Minister could last and whether National MPs would move to replace him, completely ignoring the fact that the last time a party replaced its leader in government and went on to win the next election was 85 years ago in 1940.

In all the excitement no-one dared comment that opinion polls are but a snapshot in time, so cannot be considered in isolation. The trend they disclose is far more significant than the result of any individual poll. In that regard, the long-term rolling average of polls still shows the coalition government having the numbers to form a government, even though its majority would be smaller than at the last election. Moreover, only once since then – in March this year – has the polling average showed the Labour/Greens/Te Māori bloc ahead of the coalition government.

One trend that all the polls has showed since February this year has been steadily rising support for New Zealand First. Consequently, at this stage, New Zealand First’s performance looks like being the largest determinant of the result of next year’s election and which group of parties will form the next government. And it is therefore worth recalling that in its four stints in government New Zealand First has twice worked with Labour and twice with National, so potentially could work with either side once more, allowing the commentariat to trot out the “kingmaker” label yet again.

However, New Zealand First’s influence on next year’s election outcome is likely to be different from the traditional post-election dance it has engaged in when in a position to do so. Since 2023, New Zealand First has consistently and frequently ruled out working again with Labour under Hipkins’ leadership, due to residual bad blood from the 2017-2020 coalition experience. On that basis, with Hipkins looking increasingly entrenched as Labour’s leader, at least until the election, it seems reasonable to assume that New Zealand First will not be part of any governing arrangement with Labour so long as he is around.

But that does not mean that New Zealand First will have no influence on whether Labour leads the next government. Its influence will come from the size of its vote share at the election. In short, the more votes New Zealand First garners, the less likely it will be that Labour will be able to form a government.

At present, the soft votes National is shedding look to be going to New Zealand First – they are not crossing the line to Labour. On present numbers, to be able to lead a government after the next election, Labour needs to be converting to its cause more of those voters now deserting National, rather than seeing them just decamp to New Zealand First, and remain within the coalition’s bloc.

This is especially so with support for the Green Party on average hardly having moved above the support it had at election time, and Te Pati Māori’s volatility as a potential governing partner. Labour therefore needs to be actively going after the voters now switching to New Zealand First from National, rather than lethargically standing by, as seems to be the case at present. Otherwise, the likelihood it will be able to form a government after the next election will be lower.

New Zealand First poses just as big, though different, a problem for National. While New Zealand First’s increasing support is not yet threatening the coalition’s hold on power, it is threatening to destabilise its dynamics. At the last election, New Zealand and ACT together accounted for 28% of the coalition’s voter support – on today’s current polling average they make up almost 36% of its support. New Zealand first’s proportion has risen from just under 12% of the coalition’s vote at election time to almost 18% on today’s figures. To maintain its grip on power and not have its influence further reduced, National will therefore also be keen to see New Zealand First’s current support diminish, and for those voters to return to National at the next election.

While National and Labour continue to be portrayed as wallowing, the opportunities for New Zealand First and to a lesser extent ACT will prosper. Given that ACT has nowhere else to go politically than supporting National, New Zealand First with its record of having previously worked with both sides of politics seems set to continue to gain from voter disillusionment, at least in the short-term.

That is why New Zealand First’s next election result will probably determine who forms the next government, and why, for different reasons, it is in National’s and Labour’s interests for New Zealand First’s support to be brought to ground before then.