Final nationwide polling update
A brief check on the overall nationwide picture based on the final polls.
Despite a potential late swing towards Labour and the Greens, the accompanying swing to NZ First means the overwhelmingly likely outcome of the election is NZ First entering some kind of arrangement with National and ACT.
The big picture
In terms of the latest poll tracking, National (35%) hold a substantial lead over Labour (27%). Figures for the Greens (14%) and TPM (2.5%) give the left a combined 44%. ACT (9%) and NZ First (7%) give the right a combined 51%, for a 7% lead.
TOP are on 2.4%, other right parties combined 1.4%.
Trends
Labour reverse some recent losses in the final stretch (+1.4). Green gains continue (+1.5). NZ First recover (+2.1). National give up some recent gains (-2.1) while ACT's slide continues (-1.8). TOP up (+1.4). TPM and the miscellaneous right stable.
The overall polling phase over October has been 🟢<🔴=⚫<🔵<🟡 or "leftwards" compared to September’s 🟢<🔴⚫>🔵<🟡 "towards National and the Greens" phase.
Breaking down polling by firm, there’s a reasonable consensus among firms. Roy Morgan’s September numbers are still not available, and given the delay may not be useful anyway.
Seats in the house
NZ First’s recovery to over the threshold combined with National and ACT’s relative decline means NZF will be necessary to form a government. Combined the right have 66 seats, the left 55.
The death of the ACT candidate for Port Waikato also means National will almost certainly have an overhang seat once the byelection is completed, leading to a 121 seats house at minimum.
There is also a possibility Te Pāti Māori create an overhang, but we have not modelled this.
Were TOP to win Ilam, they would have three seats, one each from National, the Greens, and ACT.
Performance relative to polling
Polling error is impossible to predict with any accuracy. An error in the previous election does not mean there will be one in the same direction this time.
However, there are fairly consistent patterns.
National and the Greens underperform
Labour and NZ First overperform
On an individual party level that averages and 95th percentile ranges are:
🟡ACT: -0.3% (-2.2% to +1.6%)
🟢Gre: -1.0% (-2.9% to +0.9%)
🔴Lab: +1.4% (-2.3% to +5.0%)
🟠TPM: +0.2% (-0.2% to +0.6%)
🔵Nat: -1.3% (-4.8% to +2.2%)
⚫NZF: +0.27% (-1.7% to +2.2%)
We can use these tendencies and the uncertainty associated with them to estimate the range of plausible outcomes once votes are counted.
Election day outcomes
Top line numbers - National highly favoured
The move to a likely 121 seat house means hung outcomes (ignoring other overhangs and Ilam) are impossible. Otherwise the overall position points overwhelmingly to a National victory, even accounting for a Labour’s tendency to over-perform their polls.
Shape of coalitions - NZ First required
Much more significant shift in the likely government formation. With NZ First recovering enough to make their odds of entering house ~97%, they will almost certainly be required to govern.
Labour’s paths
Labour's chances come from two situations.
Where NZ First miss out (3%), they have the numbers 61% of the time, or 2% of all cases.
Where NZ First make it in (97%) they have the numbers only 3% of the time, or 3% of all cases.
The sum of these situations gives their 5% odds. A narrow path, but about the odds the bookies were giving of Fiji beating Australia at the men’s rugby world cup so…
If Ilam…
An addendum on the effect TOP winning Ilam could have. (The electorate and nationwide models are not integrated so can't be run together). Were Manji to win, TOP would have the balance of power 17% of the time. This lowers Labour's chances to 1%, and National's to 82%.
Latest estimate of Manji's chances were approximately 18%, so combined they have a 3% chance of being able to choose between National's bloc and Labour's.
That’s all for today. Will be sending around a final update on seats and a “what to expect” primer about the swings from polling, through early votes, votes on the night, and specials.