The party’s best hope of returning to power is to stay high in the polls while knocking NZ First under the threshold. Bridges is under huge pressure today after the Jami-Lee Ross saga, but his MPs would be foolish to start apeing Labour’s approach to leaders in opposition, writes Liam Hehir

The question of Simon Bridges’ grip on the National leadership has been bubbling around for a while. He has suffered a few missteps of late – which seems to account for much of the amateur Kremlinology on the subject. Tellingly, there has been little emanating from the National Party itself – apart from the pesky matter of the early leak of Bridges’ leadership expenses in August.

Except that, as of lunchtime yesterday, that minor irritation was transformed into a splitting headache. Bridges announced to the media that, as the result of an investigation, he considered that Botany MP Jami-Lee Ross was behind the leak of his travel expenses in August. Moments before, Ross had taken to Twitter to out himself as the accused and as a malcontent within the National caucus.

Party MPs meet today to decide whether Ross will remain among their number, but we’re unlikely to get a quick answer on how it’s all playing with the public. New Zealand was once a land awash in published opinion polls, which meant we had a good idea about which things resonated and which ones didn’t. But public polls are thin on the ground these days. Some people are lucky enough to see private polling – but it’s something of a hack move to base you public analysis on such things.

Nevertheless, it is clear that there has been no great collapse in support for National so far. Support for the party remains in the mid-40s. The overwhelming majority of the caucus have been safe in their jobs. Bridges trails badly in the preferred prime minister stakes but it’s the party vote that counts, as people seem quick to forget whenever remembering is not convenient.

When a party is three or four points away from being able to govern alone, it is not the time for that party to change leaders. This is what will infuriate National supporters about Ross’s behaviour. All things considered, the party has been holding up pretty well.

Which is not to say there were no dangers to Bridges. There always are in politics. For the leader of the opposition, the biggest danger right now is National losing its nerve. And it is crucial for the party that it continues to hold its nerve in the face of the Ross saga.

It may come as a surprise to the echo chambers of government-supporting social media, but National and its supporters feel that the shine is starting to come off the Labour-led government. Ministers have resigned or have been removed from office in disgrace. Questions have been raised about the PM’s honesty. New Zealand First, Labour’s junior coalition partner, has been acting out like an attention-seeking toddler.

But people really tend not to vote on such things. If National won’t lose much support over Jami-Lee Ross in the longer term, it also won’t gain much through the misadventures of Clare Curran. Give voters their credit: they’re much more likely to vote on substance and to forgive a bit of bumbling at the margins.

Single-term governments are exceedingly rare. For the opposition, dethroning any first-term prime minister is a bit like winning Lotto. It’s great if you can pull it off, but it’s not to be assumed. The most National should be expecting for 2020 is to give the government a real run for its money and inflict enough wounds to set itself up for 2023.

If National loses sight of this now then the result will be lethal. Few things are as destabilising as frustrated hope – even if that hope is realistic. When you’re well off the pace, limping across seems like an achievement. If you think you should be winning, coming in second will drive you insane.

Let’s say National did lose its nerve and decided on a different direction. What would that look like? Where would it go? There are two possibilities.

The first is a high-hanging fruit strategy. Upscale liberal voters would be tempted with a Diet Coke version of Jacinda Ardernism, trying to beat the prime minister at her own game. The problem, of course, is that the party relies on conservative supporters and voters – and that can’t just be wished away. An aggressive and outward attempt at modernisation by National would look like a mid-life crisis.

You know those forty-something dads who reinvent themselves as woke centre-right guys on Twitter? Imagine that, but in political party form. It would not be a dignified thing.

The second is for National to go Tea Party, suppressing its moderate strands to indulge in culture war aggression. The reality is that this probably would increase the leader’s preferred prime minister rating. It might hit somewhere between 20% and 30%. But it would cede the middle ground to Labour and devastate the party vote.

Neither of these paths is particularly conducive to National recapturing government in two or five years.

It’s now a year since Winston Peters installed Jacinda Ardern as prime minister. From that moment on, the path back to power for National has been clear: push NZ First under the threshold. If you think there is some option that involves allying with Winston Peters instead, you don’t know what you’re talking about.

So National has to maximise its party vote while trying to push New Zealand First under 5% in a general election. It’s not entirely within the party’s power to make that happen, of course, but it can keep the possibility open. So far, Bridges has actually done a good job of holding National together – although that’s something that now looks like it’s going to be put through the test.

If National MPs are smart, they’ll do what they can to make it happen. That’s not to say that there aren’t MPs dumb enough to upset the one viable strategy the party has for the next six years. We all know there are vain and short-sighted people in all political parties. But if the caucus as a whole decides a National version of the Goff-Shearer-Cunliffe-Little carousel is a good idea then, frankly, it deserves to lose.