If Polanski Wins, Labour Loses?

This week in politics has been of great significance for those on the British Left. Following Zarah Sultana’s resignation from the Labour Party, there has been confirmation of plans to create a new party of the Left, centered around Sultana and Jeremy Corbyn. Polling by More in Common suggested that this new party could achieve 10% of the vote in a general election, with the gains mostly coming from the Green Party and Labour. However, the more significant story for the future of the Left is the beginning of the Green Party’s leadership election campaign. Not only does the strategic direction of the Green Party lie on this ideologically divided contest, both Labour and the New Left party will be affected significantly by a Zack Polanski victory. Polanski wishes to lead the Greens with what he describes as an “eco-populist” ideology. aiming to court young, diverse, working-class voters who have appeared apathetic to Labour’s first year in government.

For the first time in decades, it appears though there is a real possibility that Labour will face an electoral threat from the Left. The 2026 Local Elections are being held primarily in Labour run councils, which both Polasnki and the new Left party plan to attack in an attempt to damage Labour and force the government leftwards. Despite a growing threat from the Left, Starmer and his cabinet have been laser-focused on slowing the growth of the insurgent Reform UK. Starmer’s strategy may be a historic miscalculation, the door is now open for two left-wing alternatives, who are hellbent on giving Labour a bloody nose.

In his bid to move from Deputy Leader to the top job, Polanski is facing off in a two-month contest against co-leadership candidacy from North Herefordshire MP Ellie Chowns. and Waveney Valley MP Adrian Ramsay. Ramsay has led the party alongside Carla Denyer since 2021, with relative success; the party increased its vote share from 2.6% to 6.7%, winning four seats in the process. But Polanski is far more ambitious, he is aiming to replace Labour as the largest party of the British Left. The Green Party’s 2025 Leadership Election is unprecedented for a party which is often seen as factionless due to its collective policymaking. This contest is poised to be the closest, and most ideologically divided in recent memory, with Polanski representing the radical “Eco-socialist” wing, and Chowns/Ramsay embodying the moderate, pragmatic “Realo” wing. Members of the Greens face a clear strategic choice: remain a cautious minor party with steady growth, or transform into a party willing to challenge Labour and Reform head on. Historically, the Greens have avoided the factional warfare typical of Labour, but this leadership contest has the potential to create a clear dividing line in the party along economic and strategic lines. Although Polanski pitches himself as an outsider, his chances are very real; the Green membership is younger, more radical and more economically left-wing than the party’s representatives in Westminster. Research from Novara Media suggests that the Green Party has seen a surge in membership since May, growing from 60,000 to over 65,000, much of which has been attributed to Polanski’s campaigning. Driven by a combination of combative social media posts and traditional TV/Radio appearances, Polanski has rarely left the spotlight in recent months. This could not be more different to his opponents, who have run extremely low-profile campaign which has yet to captivate the party base or attract wider media attention.

Should Polasnki succeed in his bid for leadership it would represent a substantial ideological change for the Green Party. If you’ve heard Polanski speak even just once, you will be aware of his efforts to highlight the intersection of “Racial, Social. Economic and Environmental Justice”. Polasnki intends to turn the Greens into a party that is present in working-class communities across England and Wales beyond election days. He was pivotal in the launching of Greens Organise, an eco-socialist group that plans to “organise” the internal affairs and communications of the party while moving it significantly to the left. Greens Organise has been described by critics and supporters as taking inspiration from Momentum, the Socialist organisation that supported Jeremy Corbyn as Leader of the Labour Party. A Green Party under Polanski may have more to do with Jeremy Corbyn than just political strategy, it appears as though Polanski is pitching the Green Party as willing participants in an electoral alliance with the new Corbyn/Sultana party. Polasnksi has been aggressively courting disaffected Labourites throughout his leadership campaign, including Zarah Sultana, who he hoped would defect to the Greens. Following Sultana’s bombshell announcement last Thursday, Polanski extended another olive branch by remarking “Anyone who wants to take on the Tories, Reform and this failing Labour government is a friend of mine”.

A Polanski victory in the Leadership Election could lead to a Green-Left alliance capable of overtaking the Liberal Democrats in the polls on day one. A Green-Left electoral pact would set its sights firmly on Labour’s century long urban strongholds and would finally see significant gains for the non-Labour left outside of London. Although speculative a Green-Left alliance polling at 15% while Labour languishes in the mid-20s could plausibly secure 40-60 seats, with victories not only in London but across Liverpool, Leeds, Manchester, Sheffield, Birmingham, Bristol, Norwich, Exeter, Brighton, Cardiff, Edinburgh, and Glasgow.

Labour faces a strategic dilemma if a Green-Left Alliance is formed in the coming months. Under Starmer’s leadership Labour lost significant portions of their “Red Wall” heartlands to Reform UK at the 2025 Local Elections; come May 2026 Labour risk losing hundreds of urban council seats to a mixture of Green, Socialist and Independent groups. Having to balance their broad but shaky coalition may result in Labour failing to appeal to both Reform and Green curios voters. There has been a growing push by the Blue Labour faction to target Reform voters more heavily under the assumption that progressive voters will stay loyal to Labour no matter what, but this gamble is appearing to backfire after just one year of governance. Starmer’s policy of limiting the influence of the Socialists and Soft-Left within Labour has been vital in the steady rise of the Greens from 7% to 10% since the last election. The isolation of popular MPs like Corbyn, Sultana and McDonell has signalled to left-wing voters that they are no longer welcome in the Labour Party. This is what has made Polanski’s proposals all the more appealing to those on the Left, his emphasis on solidarity with Palestine, wealth redistribution, and careful opposition to NATO are reminiscent of the Labour Manifestos of 2017 and 2019.

With a view to the distant, the long-term question for the Green-Left project is whether to pursue an alliance capable of governing with the Labour Party in the style of France’s “New Popular Front” or attempting to overtake and squeeze Labour out entirely. Although a Green-New Left-Labour alliance could rely on 30-40% of the vote and would have the potential to form a government, the strategy that appears the most rewarding for Polanski and Co is replacing Labour as the party of the left as early as 2029! A More in Common poll conducted in late June showed, a “Corbyn-led” party would poll at 10%, the Greens 5%, and Labour 20%. This would place the Green-Left just 5 points behind an unpopular Labour government, with as many as three years to pass Labour in the polls and demonstrate to voters that they are the force that can prevent Reform from taking power in 2029.

The 2nd of September, the date of the Green leadership result, may prove pivotal for both the Green Party and the wider Left. Should Polanski succeed in his leadership bid, and Sultana/Corbyn succeed in creating their new party, Labour’s century-long domination over the Left could be shattered in a matter of months. This would open the door to a chaotic run towards the 2029 General Election: five parties above 15% in the polls and SIX parties capable of returning upwards of 50MPs.

Written by Oli (Green Party Member) @oae3108