Zack Polanski has fixed the Green Party's biggest problem.

We don't have to agree on everything. We just have to have common cause.
- Zack Polanski

Zack Polanski’s first weeks have shifted the Green Party’s centre of gravity. Polanski has rebranded the Green Party from a stagnant caricature of rural protest, to the centre of left-wing organising, and now the best-placed vehicle to face Reform UK.

Polanski was elected leader on 2 September with a decisive 85 percent mandate. The choice was simple: keep the status quo or back Polanski's Bold Politics. The result punctured the lazy story that the Greens are a club for Westminster insiders and rural Tories, and signalled members’ appetite for a left-populist programme aimed squarely at renters and low-paid workers. If the surge holds, the Greens seems inevtiable to become the party the left will rally around to face Reform and the wider far right.

With Jeremy Corbyn and Zarah Sultana’s project faltering before it even has a name, a Polanski-led Green Party is well placed to attract left-minded voters in search of a home. Signalling a big-tent approach in his victory speech, Polanski quoted an old New York line repopularised by democratic socialist NYC mayoral candidate Zohran Mamdani, "If you agree with me on 9 out of 12 issues, vote for me. If you agree with me on 12 out of 12 issues, see a psychiatrist". The point lands because the audience has changed. The Greens are welcoming organisers from trade unions, campus groups and community campaigns who want action first and ideological purity second.

That influx is already measurable. After the Corbyn–Sultana split went public, the Greens gained nearly 1,400 members in 24 hours and have now pushed total membership past 77,000, more than a 10 percent rise since Polanski became leader, with many more also joining prior to Polanski's election specifically to vote for him. Today, per Lord Ashcroft Polls, the Green Party achieved their highest ever poll rating of 13%, placing them above the Liberal Democrats for the first time. This is what a movement looks like when it finds a credible vehicle.

Polanski is also defining the Greens against both Labour and Reform UK. He has ruled out deals with Keir Starmer, framed Nigel Farage as a charlatan, and tied climate to the cost-of-living crisis with an unapologetically working-class pitch. This is the fix for the party’s long-standing problem: swap the image of a rural pressure group for a mass membership party that speaks to wages, rents and bills as clearly as it speaks to clean air and warm homes.

Why is everything so shit? Our wages are shit, our rivers are swimming in shit, and most politicians, they are full of it too.
- Zack Polanski

The offer is broad and coalition-minded. Across the Atlantic, Mamdani's campaign for New York mayor, pulling together renters, workers and immigrant communities behind a practical left platform has been incredibly successful. In the primary Mamdani surged from just 1% in polling to winning decisively. Polanski has taken clear inspiration from Mamdani adopting a laser-focus on a compassionate economic agenda, and vocal resistance to the far-right.

Labour keeps inching right in a doomed attempt to appease Reform-curious voters. Reform UK promises change, yet its brand of change is the same old cruelty of the Reagan and Thatcher playbook, dressed in new colours. Until Polanski's election, Reform have been the only party offering radical change rather than incremental adjustments, so it is unsurprising that as everything in the country broke, so many turned to them for a novel solution. Polanski’s wager is that you can meet the desire for change without scapegoats, and that compassion and respect beat demonisation and intolerance when tied to material wins people can feel.

The next tests, particularly the 2026 local elections , will tell us if this sticks, and whether the Green Party can truly challenge Reform. Alongside ongoing efforts to reunite with the Scottish Greens. However, it is undeniable that Zack Polanski has rebranded the Green Party from a party for rural protest votes with hopes of getting 5 or 6 seats in the next election, to the centre for left-wing activism - aiming to win over 40 seats, and currently it seems they have the momentum to prove this.

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