National slumps to new low - is Luxon the problem?

Analysis: National appears to be baked in as a party of 30 or below with at least eight reputable polls this year, including the recent RNZ-Reid Research, having the party slump into the 20s.

Leader Christopher Luxon and many of his senior ministers have skipped the country this week - taking the opportunity to get a final break in before the election.

News that his party has polled at 28.7 will be unwelcome, and certainly no Hawaii holiday tonic.

It's difficult to know who has the worse job at this point - Luxon, or his campaign chair Simeon Brown, who was handed the mantle of trying to turn the ship around with an unpopular leader and a resurgent New Zealand First.

National's result in RNZ's latest poll has the party crashing to its lowest level of support since Luxon became leader, and it's also the fourth consecutive decline for National since May last year.

On the other hand New Zealand First seems to be reaping rewards from National with its third consecutive increase in this poll, and its strongest result in the Reid Research series in nine years.

Despite National rolling out policy that even Labour can't find fault with, such as its compulsory KiwiSaver and baby boost policy or its household solar panel loans, it can't get traction in the polls.

Voters are even starting to feel less gloomy about the economic outlook, but National is just stuck in the mud.

There's a point where Luxon might need to consider whether he's the problem.

History would suggest he's got until eight weeks out from an election to do that and his party could still have electoral success.

The counter-argument is there have been plenty of political parties win elections with unpopular leaders, and MMP has created an environment where it's less about one leader and more about the make-up of a coalition and whether it can get the job done.

On that count Luxon has defied the odds and held together an incredibly difficult three-way coalition that many predicted would never survive the term.

Managing David Seymour and Winston Peters and their parties' many policies, positions and repositions is a full-time job.

The bright spot in any bad polling that Luxon often points to is that the coalition could still govern, even if only by a whisker.

That's the case in the RNZ-Reid Research poll with the coalition collecting 61 seats if an election was held today, to the opposition's 59.

That is tight, and various overhang machinations could further complicate the calculation, especially if Te Pati Māori won more than three electorates.

The biggest problem in such a narrow election win for Luxon would be the state of his Cabinet post-coalition talks.

A bigger New Zealand First and Act would significantly reduce the ministerial portfolios and policy wins for National.

Put simply ministers in this term of government could be resigned to select committee chairs if they're lucky, backbenchers if they're not, and if they're really unlucky they won't be in parliament at all.

That's at least three reasons for the National Party MPs not sunning themselves overseas this week to be mulling how best to save themselves.

Over in camp Labour there's reason to celebrate with it holding its position of the largest party in this poll with 34 percentage points, but no obvious path to power.

That is of course unless Opportunity can get across the line, at which point it could be a kingmaker with the power to appoint either of the Chrises as Prime Minister.

The Opportunity Party more than doubled its result in our last poll in March - up from 2 to 4.7.

The other obvious place for National and Labour to be looking for votes is the undecided or non-voters in any given poll.

However, that number has considerably dropped from 7.1 percent in March to just 3.8 percent of the 1000 respondents polled between July 2-9.

It appears more voters are starting to make up their minds as the election approaches - but not to the benefit of those major parties.