National has recorded its lowest party vote under Christopher Luxon in the RNZ-Reid Research poll, dropping 2.1 points to 28.7 percent. The poll, conducted from 2 to 9 July and published on Tuesday, marks the party's fourth consecutive decline in this polling series. It was taken after the annual conferences of National, Labour and ACT and a string of policy announcements from all parties.

Labour leads on 34 percent, down 1.6 points since March. New Zealand First climbed 0.9 points to 11.5 percent — its best Reid Research result since July 2017. The Greens edged up 0.2 points to 10.3 percent, ACT gained 0.8 points to 7.8 percent, and Te Pāti Māori fell 0.9 points to 2.3 percent. The standout result is the Opportunity Party (TOP), which more than doubled its support, rising 2.7 points to 4.7 percent. That puts TOP within 0.3 points of the 5 percent threshold needed to enter Parliament without winning an electorate seat. Undecided or non-voters fell sharply to 3.8 percent from 7.1 percent in March.

On these numbers, the current governing coalition of National, NZ First and ACT would hold 61 seats in a 120-seat Parliament (National 36, NZ First 15, ACT 10), against 59 for a Labour-Greens-Te Pāti Māori bloc (Labour 43, Greens 13, Te Pāti Māori 3). That's a bare majority with little room for error.

Two factors complicate the seat count. National currently holds 43 electorate seats — the local electorates members are directly elected to represent. If it won more than 36 of those on the night, it would trigger an overhang: extra seats added to Parliament rather than redistributed from coalition partners, widening the government's margin. Te Pāti Māori won six of the seven Māori electorates at the last election and would need more than three electorate wins to close the gap with the government bloc, even on a lower party vote. And if TOP clears 5 percent, the reallocation of list seats across Parliament would reshape numbers for every other party in the House, not just add a new player.

On preferred prime minister, Chris Hipkins leads at 23.9 percent, up 3.2 points. Christopher Luxon rose 2.7 points to 20 percent. Winston Peters sits third on 13.2 percent, up 0.1. Fifteen percent of respondents either declined to answer or said they didn't know. According to RNZ, both leaders posted their lowest approval ratings in this poll — though Hipkins' preferred PM figure moved up rather than down, so the two measures aren't tracking together this round.

On whether things are heading in the right direction, 34.7 percent said yes (up 2.4 points), against 46.5 percent who disagreed (down 3.5 points). A further 17.5 percent were undecided.

Set against other recent polling, the RNZ-Reid Research numbers sit slightly differently to Roy Morgan, whose June reading showed the National-led government's combined support broadly steady at 51 percent. The 1News Verian poll from late June had both major parties at 30-year lows, with Labour down five points and TOP also closing on 5 percent. Across all three pollsters, the consistent pattern is minor parties gaining on both flanks and TOP's vote building — though the different polling companies use different methods and won't line up exactly.

What matters for governing numbers is more complex. A coalition majority of two seats leaves almost no room for a byelection loss, a defection, or an electorate-seat surprise to flip the balance. That's where the overhang scenario around National's electorate seats shifts from a technical detail to something central to post-election negotiations, because it changes Parliament's overall size rather than just the shares within it.

The TOP trajectory is the other thread to watch. A party 0.3 points under threshold, having more than doubled its support in a single poll, needs only a small swing to cross the line — the kind of movement that would put list seats in play and reshape numbers for every other party currently banking on the status quo.