Key Takeaways
- The NZ Herald‑Motu Research Poll of Polls aggregates public and private polling data back to 2014 and runs 4,000 election simulations to estimate outcome probabilities.
- Since the 2023 election, National’s support has fallen markedly while Labour’s has risen, yet the opposition still lacks a clear lead.
- NZ First’s vote share has surged to a median above 10 %, offsetting part of National’s decline and bolstering the governing coalition’s numbers.
- The Green Party’s support has gradually eroded, now sitting below its 2023 election‑night figure of 11.6 %.
- Te Pāti Māori experienced an early rise toward 5 % followed by a sharp polling crash in 2025, reducing its parliamentary presence.
- Simulations project National ≈ 37 seats, NZ First ≈ 16 seats, and ACT ≈ 10 seats—enough for a three‑seat majority—while Labour would be the largest party with ~43 seats but unable to form a government without additional partners.
- Analyst Stuart Donovan notes that votes tend to “slosh” between ideologically similar parties, creating high variability at the party level but relative stability when looking at the bloc‑wide balance of power.
Overview of the Poll of Polls Methodology
The NZ Herald‑Motu Research Poll of Polls represents a sophisticated effort to distill the noisy landscape of New Zealand polling into a single, probabilistically grounded forecast. It begins by gathering all publicly released polls as well as any private or less frequent surveys that meet basic quality thresholds. These data points, stretching back to the 2014 general election, are fed into a computer‑based model designed by Stuart Donovan of Motu Research. The model does not merely average the latest numbers; instead, it treats each poll as an observation of an underlying, latent voter preference distribution and then runs 4,000 simulated elections based on draws from that distribution. Each simulation translates party vote shares into parliamentary seats under New Zealand’s mixed‑member proportional (MMP) system, yielding a distribution of possible outcomes. The final Poll of Polls figure reflects the central tendency of those simulations—typically the median or mean seat count—while also providing probabilities for scenarios such as a coalition majority, a hung parliament, or a change of government. By anchoring the model in a long historical baseline, the approach seeks to smooth short‑term polling volatility and reveal deeper trends that might be obscured in any single survey.
National’s Decline and Labour’s Rise
One of the most striking patterns emerging from the Poll of Polls is the divergent trajectories of the two largest parties. Since the 2023 election, National’s vote share has undergone a noticeable decline, a trend that is consistently reflected across multiple individual polls and is reinforced in the model’s aggregated output. Conversely, Labour has experienced a steady, if modest, increase in support over the same period. This upward drift for Labour is not a sudden surge but rather a gradual accumulation of votes that has lifted its median position in the Poll of Polls. The simultaneous movement—National losing ground while Labour gains—creates a classic seesaw effect in the overall vote share landscape. However, the Poll of Polls cautions that these shifts, while clear at the party level, have not yet translated into a decisive advantage for the opposition bloc, because other parties’ movements are simultaneously reshaping the electoral arithmetic.
The NZ First Surge
Counterbalancing National’s decline is the remarkable rise of NZ First. Over the past twelve months, the party’s support has climbed sharply, pushing its median score in the Poll of Polls well above the 10 % threshold. This resurgence is sufficiently strong to recoup a substantial portion of the votes that National has lost, thereby preserving the governing coalition’s numerical strength. The model shows that NZ First’s gain is not merely a statistical fluctuation; it appears in multiple polling houses and persists across different time windows, suggesting a genuine shift in voter sentiment toward the party’s platform of conservatism, populism, and economic nationalism. Importantly, NZ First’s rise has occurred without a corresponding drop in Labour’s support, indicating that its new voters are likely drawn from disaffected National supporters, centrist voters, or even former ACT backers who find NZ First’s stance on issues such as immigration and fiscal prudence more appealing. This realignment has been a pivotal factor in keeping the coalition within striking distance of a majority despite National’s weakening position.
Green Party’s Gradual Erosion
On the left‑wing side of the spectrum, the Green Party has experienced a slow but steady erosion of its vote share. The decline has been so incremental that, in any single poll, it might appear negligible; however, when viewed over the longer horizon captured by the Poll of Polls, the trend becomes unmistakable. The Greens’ median score has slipped below the 11.6 % they secured on election night in 2023, reflecting a gradual loss of support to both Labour and, to a lesser extent, other progressive or environmental‑focused micro‑parties. This steady bleed suggests that while the Greens retain a core base of committed environmental voters, a portion of their softer‑aligned electorate is being swayed by Labour’s modest leftward shift or by issue‑specific concerns that the Greens have not adequately addressed. The Poll of Polls captures this subtle drift, highlighting that even small, consistent changes can accumulate to affect coalition‑building prospects over an electoral cycle.
Te Pāti Māori’s Volatile Fortunes
Te Pāti Māori’s polling story is markedly more volatile. After an initial uplift that saw the party flirt with the 5 % mark—potentially enough to secure list seats without an electorate win—the party’s support subsequently suffered a pronounced crash over the course of 2025. The Poll of Polls records a sharp shedding of backing, dropping the party’s median well beneath the threshold needed for reliable list representation. This downturn appears to have been driven by a combination of factors: internal leadership challenges, competing Māori‑focused initiatives from other parties, and a broader electorate re‑prioritising issues unrelated to Māori self‑determination. The consequence is that Te Pāti Māori’s contribution to any potential left‑wing or progressive coalition has become minimal, further complicating Labour’s attempts to assemble a governing majority without relying on the traditional bloc of smaller parties.
Seat Projections and Government Formation Prospects
Translating the party‑level trends into parliamentary outcomes, the Poll of Polls’ average simulation yields a seat distribution that points to a continued National‑led coalition, albeit with a slim margin. The model estimates National securing roughly 37 seats, NZ First contributing about 16 seats, and ACT adding around 10 seats—totalling approximately 63 seats in the 120‑seat Parliament. This total confers a three‑seat majority over the opposition, sufficient to pass confidence‑and‑supply motions and sustain a government. Labour, despite being the largest single party with an projected 43 seats, falls short of a workable majority because the Greens’ anticipated 11 seats and Te Pāti Māori’s modest 3 seats would only bring the opposition bloc to 57 seats, well below the threshold needed to govern alone or to form a stable coalition without additional partners. The simulations thus underscore a key feature of New Zealand’s MMP system: a party can lead in popular vote and seat count yet still be excluded from power if the fragmentation of the cross‑bench prevents a viable coalition.
Interpretation: Vote Sloshing and Bloc Stability
Stuart Donovan, the senior fellow who built the model, offers a valuable interpretive lens for these patterns. He observes that voter movement tends to “slosh” between parties that are ideologically or strategically similar rather than jumping wholesale from one ideological bloc to another. For instance, disaffected National voters may gravitate toward NZ First or ACT, while Labour’s incremental gains often come at the expense of the Greens or Te Pāti Māori. This phenomenon creates considerable volatility at the level of individual parties—evident in the wide confidence intervals around each party’s projected vote share—but it also generates a counterintuitive stability when one aggregates votes into broader blocs (government versus opposition). The Poll of Polls therefore shows that, while the exact composition of Parliament may shift frequently in the polls, the overall balance of power between the governing coalition and the opposition remains relatively constrained. This insight helps explain why, despite Labour’s steady rise and National’s decline, the prospect of an outright opposition victory has remained elusive: the votes that Labour gains are frequently offset by losses to other left‑leaning or centrist parties, keeping the opposition bloc’s total strength within a narrow band.
In sum, the NZ Herald‑Motu Research Poll of Polls provides a nuanced, data‑driven snapshot of New Zealand’s evolving political landscape. It captures the ebb and flow of party support, highlights the pivotal role of NZ First’s resurgence in sustaining the governing coalition, notes the gradual weakening of the Greens and the volatile fortunes of Te Pāti Māori, and projects a parliamentary scenario in which a slim National‑led majority persists despite Labour’s position as the largest party. The underlying dynamics—vote shuffling among ideologically proximate parties and the resulting stability of bloc‑level power—offer a coherent narrative for interpreting the poll’s numbers and anticipating future electoral developments.