UnitedFuture leader Peter Dunne has announced he is quitting politics at this election, deciding not to contest Wellington's Ohariu electorate, citing a shift in voter sentiment.

Dunne has managed to hold on to the seat at recent elections at the grace of National voters who had been asked to give their electorate votes to him by former Prime Minister John Key, and current PM Bill English.

The deal had been revived for September's election, although a recent poll showed Dunne under pressure from Labour's candidate Greg O'Connor.

The big question now will be whether National's Brett Hudson is able to get over the line for his party. Even if he does, then based on current polling the move could result in a loss of a seat for the National-led coalition as the electorate seat win would effectively push a National list MP out. (Previously I'd put that it wouldn't make a difference).

Dunne effectively endorsed Hudson, thanking at the end of his statement (below) for support over the year. No mention was made of O'Connor.

Dunne is currently Minister of Internal Affairs. He began political life as a Labour MP 33 years ago, leaving to form UnitedFuture in an attempt to raise a liberal democratic party at the centre of New Zealand politics. He served as a Minister of Revenue in Helen Clark's governments, then switching allegiences to National under John Key.

Despite many of UnitedFuture's policies perhaps being closer to Labour's base, Dunne over recent years grew more and more critical of his former party, even going as far to suggest he would not enter a coalition with Labour at the time Andrew Little was at the helm.

Alex Tarrant's take:

Perhaps this was why Dunne wasn't present at National's great unveiling of its cheaper GP visit policy in Ohariu's Johnsonville on Monday morning?

Prime Minister Bill English, Deputy PM Paula Bennett and Health Minister Jonathan Coleman were shadowed by the man who had said he wasn't even going to vote for himself in Ohariu - Brett Hudson - who was milling around there in the background.

He certainly will be changing his box ticking intentions now.

Was Dunne snubbed? This would have been a perfect opportunity for a cup of tea down the road in affluent Khandallah.

Basically the polls have been the killer. UnitedFuture didn't even feature on the 1 News Colmar Brunton poll last week. Unless it looked like UF might have been able to get to the 1.2% mark needed to bring a 'coat-tails' MP on the back of Dunne's electorate seat, there's no difference for National in terms of whether it was Dunne or Hudson who won the seat.

ACT leader David Seymour has the same arrangement in Epsom. ACT is at about half a percentage point on most polls at the moment - a bit of jump needed, but at least in a better position than Dunne. National's catering to New Zealand First voters this campaign might just see a few urbanites turn to ACT in protest, so Seymour still has a slight chance to have a mate in with him after 23 September.

I've known Dunne for a number of years - I went to school out at Onslow and played for the North Wellington football club of which he was the patron. He was always well-regarded as a good electorate MP. I had assumed that inclusion of more of Wadestown in the Ohariu electorate should have boosted Dunne's ability to be re-elected, even at the behest of National's leadership.

I struggle to understand how Greg O'Connor alone could have boosted support for Labour in Ohariu. No offence to the guy - he's a nice bloke, but he's not going to be any better as a local candidate. So that leaves me with one factor trumping the rest: The snap Ohariu poll which looks like it has sunk Dunne was taken by 1 News Colmar Brunton after Jacinda Ardern had claimed Labour's leadership.

Is Dunne the first scalp of a resurgent Labour Party under Ardern?

See Dunne's statement below:

“The current political environment is extremely volatile and unpredictable. However, I have concluded, based on recent polling, and other soundings I have been taking over the last few weeks, that, the volatility and uncertainty notwithstanding, there is now a mood amongst Ōhāriu voters for a change of MP, which is unlikely to alter. This shift in voter sentiment is quite at variance with polling and other data I have seen throughout the year, upon which I had based my earlier decision to seek re-election for a 12th term as MP for Ōhāriu. While I am naturally extremely disappointed after 33 years of service at this apparent change of feeling, I recognise and understand it, and respect absolutely the electorate's prerogative to feel that way. “I have therefore decided that it is time for me to stand aside, so the people of Ōhāriu can elect a new electorate MP. Consequently, after much consideration and discussion with those closest to me, I am announcing today that I will not be putting forward my nomination for election to the next Parliament. I do so with considerable reluctance, but I have always understood that holding public office is a temporary privilege granted by the people, and can never be taken for granted. “I have thoroughly enjoyed serving the Ōhāriu electorate in its various forms since 1984. I thank my constituents, my supporters, my Party, and all those staff members who have worked so loyally and professionally alongside me over the years, but above all, I pay huge thanks to my wife Jennifer, my sons, James and Alastair, raised in the heat of politics, and my entire family for their loyal support, patience and encouragement for so long. “I am especially proud to have worked alongside successive National- and Labour-led Governments in the collaborative environment of MMP, and to have had the privilege of serving as first an Under-Secretary and then a Minister under seven different Prime Ministers for just on fifteen years. I am very proud of the many changes I have been able to make in my portfolios over the years to make New Zealand a better place in which to live and raise a family. “Over the last three years alone, I have been very pleased to lead the work to modernise New Zealand's drug policy towards a stronger health focus; and to make fluoridation of drinking water more widespread. I was delighted to establish Fire and Emergency New Zealand which unified our urban and rural fire services in the biggest reform of our fire services in 70 years. I was also very pleased to have been able to bring back 10 year passports. The D5 group of the world’s most digitally advanced nations meets in New Zealand early next year. Having overseen New Zealand help form the D5 group in 2014, I will be very sorry not to be chairing that meeting. Lastly, I have enjoyed being part of the continuing drive to make the taonga of the National Library and the National Archives more widely available to all New Zealanders. “Ōhāriu has been a very large part of my life. I have lived continuously in the area for more than forty years. Jennifer and I raised our family in Ōhāriu. It is our home. Working for the community and its people over the last 33 years has, at all times, been an absolute delight. I will miss hugely that direct engagement with so many aspects of the life of our community, and I will never forget the huge honour Ōhāriu gave me by electing me, first as a young 30 year old, and then for the next ten elections after that. “But good things cannot last forever. Now it is time for me to put all that behind me, take the election hoardings down, say goodbye to Parliament without bitterness or regret, and get on with life. “Finally, my thanks and best wishes for the future go to Brett Hudson MP, National’s List MP based in Ōhāriu, for the support he has shown me throughout this year.”

Statement from Prime Minister Bill English: