The Green Party: Has the Polanski bubble burst?

When Zack Polanski ran for the Green leadership a year ago, he offered his party a clear new strategy.

Polanski would use bold social media-focused messaging and radical policies to win over younger progressive voters disappointed by the Labour government's failure to deliver on their priorities and turned off by the grey and dour image of then prime minister Sir Keir Starmer.

This worked well for the first half of 2026, delivering success in local and devolved elections and a first-ever Westminster by-election breakthrough in Manchester's Gorton and Denton.

But with the new Labour prime minister using bolder rhetoric to set out a more radical progressive agenda, the risk is growing that Polanski's strategy is past its sell-by date.

Much of Labour's polling recovery since Andy Burnham's arrival has come at the Greens' expense. Young progressives who switched from Labour to the Greens during Starmer's tenure are switching back in growing numbers.

Polanski and the Greens need to decide how to respond to Labour's moves to close down space on the left.

Should they focus on consolidating the gains made in the Starmer years, which could yet provide a strong platform for breakthroughs in local government and later in a cluster of Westminster seats?

Or should they continue with the radical agenda of the last year, attacking the Labour government from the left in the hope that another window of opportunity will open once the Burnham honeymoon fades?

Regardless of which way they turn, the Greens may also need to ask themselves whether Polanski remains a political asset after a turbulent first year as leader, which has seen his poll ratings fade fast.

Headline polls: Yesterday's news?

Though Labour gains from the Greens are much more evident since Andy Burnham became prime minister, Green polling had started to decline even before his arrival.

YouGov polls fielded in the party's February by-election triumph in Gorton and Denton had the Greens winning support from more than 20% of those offering a party preference, and challenging for second place overall.

It has been downhill ever since for the Greens. If we take an average of all the pollsters regularly in the field, the Greens' current estimated vote share is 11%, down 1.8 points on the average a year ago, and down over five points on the party's early spring peak.

Polanski himself may be a growing drag on the Greens' polling. Last autumn, Polanski won positive approvals from 17% of respondents on average, and was disapproved of by 22%, a -5 net rating which put him ahead of the Labour, Conservative and Reform leaders in most polls, albeit with most voters undecided.

Polanski's first year in charge has brought many more voters off the fence, but most have broken against him.

An average of 17% of respondents now say they approve of the Green leader, the same as a year ago. But an average of 43% now say they disapprove of Polanski, almost double the share of voters who disapproved a year ago.

This big negative shift has coincided with Labour installing a more popular leader and with a large positive shift in Conservative leader Kemi Badenoch's ratings.

Polanski started his tenure as leader near the top of the class for approval ratings. One year on and he is now competing with Nigel Farage for last place among national leaders.

The Greens' unusual electoral map

However, the Greens' slide in headline polling and Polanski's decline in overall approval ratings may not matter much. The Greens bring together an unusual electoral coalition, with their support concentrated among graduates under 40 and among ethnic minority voters.

These Green-curious groups tend to congregate in traditionally Labour voting city centre areas. As a result, the Greens' electoral map can be effectively divided into a minority of seats where the party has the demographic critical mass to be competitive and a large majority of seats where the party is out of the running.

This geography in turn interacts with tactical voting. In most seats, most of the time, the Greens can only act as spoilers, splitting off support from a larger and more competitive party of the left - Labour, the Liberal Democrats or the nationalists in Wales and Scotland - but with little hope of winning themselves.

In such seats, Green-curious voters know there is little hope of electing a Green directly, and a ballot cast for the Greens is more likely to help a local right-wing party by splitting the left vote.

These are the conditions where a tactical voting "squeeze" is often seen, with Green voters switching to a second-best option to prevent a local Reform or Conservative victory.

Recent evidence from YouGov suggests the replacement of Starmer with Burnham has made a tactical Labour vote more acceptable to many Green voters, who also remain happy to cast tactical votes for the Liberal Democrats where it makes sense to do so. Thus, in most seats, much of the Green vote is likely to get squeezed by a desire to see off Reform and Conservative challengers.

But this picture is very different in the minority of Westminster seats where the Greens are strong enough to be in the top two parties themselves.

Nearly all of these seats are Labour versus Green contests where the same local demographics that make a seat Green friendly also make a Reform or Conservative victory very unlikely.

The logic of tactical voting is very different in these young, diverse city centre seats. Green supporters have no reason to accept second best, and the Greens can instead appeal to local Labour voters by arguing a Green vote is low risk and could help deliver a stronger Green Westminster presence.

Polanski's radical left populism may play particularly well in such seats, where he can argue Green victories will put pressure on the larger Labour Party by showing it cannot take younger voters in big cities for granted.

The Greens could yet achieve many breakthroughs in the minority of seats where local conditions favour their politics even while going backwards everywhere else. This is, after all, exactly how the Liberal Democrats achieved their best election result in a century two years ago.

Election results: Green gains in Green-friendly terrain

Election results over the past year add credence to the idea that the Greens are well-placed to break through where local conditions are favourable.

The Greens made big gains in this year's English local elections, and this advance was heavily concentrated in exactly the young and diverse urban wards of London and other large cities where the party could campaign as a low-risk left-wing alternative to a locally dominant Labour Party.

Devolved elections in Wales and Scotland paint a similar picture. Both of the Greens' Senedd seats came in Cardiff constituencies, and the Scottish Green Party's two constituency gains came in central Glasgow and central Edinburgh.

And the Greens' historic by-election victory in Gorton and Denton in February, by far their best ever Westminster by-election performance, came in an urban Manchester seat with lots of students, young professionals and Muslims, where the Greens successfully campaigned as the strongest local opponent to Reform.

The Greens currently occupy a very clear niche. They are winning where they can run to the left of Labour in areas where their core demographic groups cluster together. And while such places will only ever be a minority of the seats up for grabs, that still leaves the Greens with plenty of opportunities for growth at present.

There are hundreds of council wards the party can target in coming years, and 40 Labour-held Westminster seats where the Greens start in second place.

The Polanski strategy may no longer be delivering national polling gains, but it is still potent as a more targeted campaigning approach.

This is the fourth in a series of articles reviewing the polling and electoral performance of the parties as they gather for their annual conferences. Previous versions have covered the performance of Labour, Reform UK and the Liberal Democrats

(c) Sky News 2026: The Green Party: Has the Polanski bubble burst?