Have the Greens become a major party?
Since London Assembly Member Zack Polanski was elected as the leader of the Green Party of England and Wales, the party’s fortunes have been completely transformed. In just three months, the Greens have risen from 10% in the polls to 16%, surpassing the Liberal Democrats and nipping at the heels of both Labour and the Conservatives.
While the unprecedented polling growth has been the key focus of many political commentators since Polanski’s election, the growth in party membership is arguably even more impressive with the party almost tripling in size from 65,000 to 175,000 since September. This is a major achievement for the Greens as they are now Britain’s third largest party, and Europe’s largest Green Party.
According to Green Party officials, the rapid expansion of the party’s membership has increased their annual budget from £5 million to an estimated figure of at least £10 million. This is vital to the traditionally cash-strapped party as it will allow them to aggressively contest a whole host of local elections in May 2026, where the insurgent party is looking to deal a fatal blow to Keir Starmer’s deeply unpopular government. While the Greens main focus is winning council seats to act as a springboard for future Parliamentary target constituencies (in line with their Target to Win strategy) the Party also have their eyes set on Mayoral elections in Hackney and Sussex, as well as winning their first seat in the Welsh Senedd.
However, since their rise in the polls, the Greens will be having much grander ambitions than a few mayoralties or council seats. The next general election looks to be the most fragmented and open contest in British electoral history, and this will provide the Greens with the opportunity to expand monumentally.
The path to a parliamentary majority for any party will be extremely tough, and a Left Bloc of the Green Party, The SNP, Plaid Cymru, and “Your Party” may be in a position to act as kingmaker, or to force a fractious right-wing coalition. Current estimates see the Greens rising from four seats to as many as 50, this would be entirely unprecedented for the Greens as until 2024 they had only ever won one parliamentary constituency.
A 50 seat Green Party would spell disaster for prospects of a two-term Labour government, as a majority of these seats would be won in traditional Labour strongholds where the Greens were made electorally irrelevant due to the popularity of Corbyn in urban areas. 50 seats for Polanski’s Greens would see wins in London, Birmingham, Manchester, Liverpool, Cardiff, Leeds, Sheffield, Bristol, Brighton, Exeter, Reading, Oxford, Cambridge, Norwich, and Huddersfield.
The sudden explosion in Green Party support in the North of England and London will not come as a surprise to those who have examined the Greens’ new electorate. Half of 2024 Green voters had voted Labour in 2019, whereas in 2015 only 1 in 7 Green voters had supported Labour at the previous election.
A far cry from the classic Green Party image of well-off, Europe-obsessed, environmentally conscious “Tories on bikes” that had existed until 2019, the 2024 Green Party had an electorate much closer to Corbyn than Clegg or Cameron. The new Green Party has built a coalition comprised of those who have been turned off by Labour’s pivot to the centreground; young voters, left-wingers, ethnic minorities, and urban workers.
This rapid transformation of the Green Party’s electorate will have caught the Labour party by surprise, threatening the status of several Labour ministers. Key Starmer allies Darren Jones, Peter Kyle, and David Lammy are all set to lose their seats, with Starmer himself at risk of losing his seat if “Your Party” and the Greens can get behind a single candidate in his Central London constituency.
The Green Party of England and Wales have clearly learnt from the failures of their European counterparts. Across Europe, Green Parties have stalled due to a decrease in the salience of environmental issues and largely unsuccessful collaborations with centrist parties that have damaged their reputations as a viable alternative to the status-quo. But by aggressively challenging Labour on economic and foreign policy failures, the Greens have carved out an electoral space for themselves as a home for left-wing voters.
However, there is a challenge for the Greens that may dent their sudden polling growth, Jeremy Corbyn and Zarah Sultana’s “Your Party.” Although Polanski recently issued a tongue-in-cheek invitation to Sultana to join the Green Party, it appears as though she is set on establishing a new party alongside Corbyn and other Socialists. While there is a tendency in mainstream coverage to view
“Your Party” and the Greens similarly, there are significant ideological differences between the two parties. Many on the Socialist left have derided (former Liberal Democrat) Polanski’s leftwards shift as political opportunism, rather than a sudden interest in Socialism.
With the possibility of electoral annihilation for Labour in 2026 and beyond, both left-wing parties will want to emerge as the singular force to take the fight to Reform and the Tories, and reap the benefits of a winner-takes-all electoral system. But should they resist temptation to fight each other, Polanski, Sultana, and Corbyn will have the chance to form an alliance that is entirely capable of winning 20% of the vote and over 100 seats, which would reshape British Politics entirely.
Figures within the Labour Party have already proclaimed the Greens’ recent success as a short-term phenomenon that will be subsided by threats of vote-splitting leading to a Reform majority government in 2029. However, the Greens and Labour are already in a situation echoing Reform and the Tories in early 2025. Reform’s strong showing in May’s Local Elections proved that they were a viable electoral force in a first-past-the-post system and saw them rise from 25% to 30% in the polls over the following month, while the Tories fell from 22% to 17%. Should the Greens perform well next May, they could overtake Labour nationally and become the leading left-of-centre party in hundreds of seats.
The Green Party are currently placed between 12/1 and 18/1 to achieve the most seats at the next General Election, a position that has shortened massively in recent weeks. While it is highly unlikely the Greens get the most seats in 2029, there is a good chance that these odds continue to shorten. The upcoming Budget appears to contain further cuts to spending that if poorly received nationally, will boost the Greens’ electoral prospects.
The Greens will be well placed to lead opposition to the budget, as Reform UK have signalled support for Labour to enact more austerity, and even pushed the Chancellor to go further on cuts. As seen during Labour’s new immigration reforms, the Greens have benefitted massively from Polanski’s ability to further the narrative that Labour are aping Reform UK. An increased focus on the economy will allow the Greens to further highlight areas of ideological agreement between Farage and Starmer.
Written by Oli (Green Party Member)