John Key checks out. The game has suddenly changed

John Key has changed the political game. The most popular Prime Minister in decades quits next Monday. Can Labour pick up the ball?

As December reshuffles go, yesterday’s was as big as they come.

As Key said at his press conference, he had in the past “taken the knife” to others in National’s cabinet and caucus, to refresh his government.

In 2014 a quarter of his caucus went, an unheard-of “peacetime” cleanout. Usually, it takes a big election loss to cull a caucus.

Now, Key said, he is “taking the knife to myself”.

And that is at a time when National is averaging 48% in polls and has an average 8% lead over Labour-plus-Greens combined. National had, with Key, reason to think it could get a fourth term, the first since Sir Keith Holyoake squeezed back in 1969.

Key’s stated reasons boiled down to him not being able to look interviewers in the eye and commit to serve out the whole of a fourth term if he won, to him not being a “career politician” and to give wife Bronagh and the kids a better deal.

So, quit while on top.

Conspiracy theorists and amateur and professional analysts will look for other explanations.

For example, his 2014 biographer, John Roughan, quoted him as saying he gave up rugby when young because he did not like being tackled.

And there is reason to think some tackles lie ahead of National.

One is the likely need to deal with Winston Peters to form a fourth-term government. Such a government would be less readily manageable than the coalitions-with-tiddlers Key has had through his three terms.

English and non-career-politician Steven Joyce would not have relished that and might have moved on, leaving big holes. The cabinet’s cohesion would have been strained. Would Key have served out the whole of such a term? Unlikely.

A second potential tackle is the house market or, to be precise, the impact of a rise in mortgage interest rates which would put a lot of borrowers under stress or even underwater, as Americans say.

The real impact of such a rise would be more likely after next year’s election even if it started before. And Key’s high-empathy personal popularity, in part built on the sunny optimism he exudes, would have taken a hit.

A loose parallel would be the sudden jump in inflation and then a huge petition against a high dam on Lake Manapouri that buried the post-1969 fourth-term National government.

But Key, as his sudden unforced departure shows, is not the usual “career-politician”. He wanted to be Prime Minister from a young age, came back in 2001 from offshore to do that, learnt politics fast, cleaned out a sitting National MP and, once in Parliament, scooted up the ranks.

He was not a policy wonk, which often showed in his early political years. But he did big, risky trades in his previous life and to do that he had to swot. As Prime Minister (and as a student who liked being on the squash court), when he swotted he could get on top of a topic.

As a manager he followed trading floor practice and devolved responsibility to his ministers, periodically calling them to account.

That gave wide scope to the chief policy wonk and innovator, Bill English, whom Key anointed yesterday as his successor, though English is low on charisma and as a leader in 2002 got the lowest major-party vote since 1902.

The word has been that English has been hoping for a big after-politics job, having been a career politician since 1990. But, as Labour’s Mike Moore said when he took the hospital pass within weeks of the 1990 election when Labour was doomed to defeat, you don’t say no when you can be Prime Minister.

There are others who will see themselves as contenders, not least Paula Bennett, whom Key has promoted over the past two terms.

Whoever takes over will not have the personal appeal of “macro-personality” Key, who has probably been worth upwards of 5% in National’s polling.

The question is where that outflow will go.

One destination is likely to be Winston Peters. Part of Key’s appeal was populist — his blokeyness. If Peters picks that up, New Zealand First could be headed into double figures from its current 9% poll average.

Can Labour pick up some of it?

The Mt Roskill by-election gave Key, who campaigned hard there, a poke in the eye. (Did it contribute to his decision to go?)

Mt Roskill also gave a desperately needed morale boost to Andrew Little and to Labour, which had a November poll average of around 27%. The mood in Little’s office after Key’s announcement was chipper.

At the least, Key’s departure gives Little some air. Labour leads on housing policy and is gradually grinding down its policy messages to middling voters’ practical issues, issues that will sharpen if the house market goes sour.

And gradually, Labour is learning to live with the Greens and will have something big to say next month about their joint bid to “change the government”.

They are a bit late. Key has changed the government. Without him, it will look and feel different. So will politics.