The Green Party's annual conference in Brighton this weekend takes place under very different circumstances than six months ago, when the party's shock by-election victory sent a tremor through UK politics.
In March, Zack Polanski and his colleagues overturned a huge Labour majority in the historically safe seat of Gorton and Denton, a win that accelerated Keir Starmer's political demise. The result suggested the Greens, already holding a record four MPs after the general election, could help fracture the two-party system that has dominated for over a century.
Poll ratings slide since spring surge
By October, however, the picture looks less rosy. The bump in the polls has largely subsided, and Mr Polanski's own ratings are not where he would like them to be. Next Thursday, the leader faces a reckoning in the Holborn and St Pancras by-election, triggered by Mr Starmer's unexpected resignation as an MP.
A Green victory there would be monumental: the former PM secured an 11,000 majority and the seat has been a Labour stronghold for decades. As one Green spinner put it, the fact that Mr Polanski is even being discussed as being in a two-horse race is a sign of how far the party has come. In 2024, Mr Starmer picked up over 18,800 votes, while the Greens received just 4,000.
Party squeezed by Labour's revival
If he falls short, Mr Polanski can take heart, but some within the party may quietly wonder what might have been. Despite considerable gains over the past year, latest polling suggests the Green bubble has burst. In early March, polls put the party on around 21% of the overall vote, with some suggesting they were challenging for second place. Most pollsters now place them around the 11% mark and back down in fifth.
The party may be a victim of its own success. By winning in Gorton and Denton, it set off a chain of events that significantly weakened Mr Starmer and contributed to his decision to resign.
Now Andy Burnham is making the kind of arguments left-wing voters want to hear, for example on the Middle East, nationalisation and Brexit. His barnstorming speech at the Labour conference on Tuesday highlighted a party that has its mojo back after a couple of troubled years. This is squeezing the Greens, and YouGov polling this week showed that over the course of Mr Polanski's leadership, the party's net favourability rating has fallen from +5 to -19.
Polanski urges voters to 'watch Labour move'
Mr Polanski has decided his most effective gambit is to claim credit for the government's change in direction and suggest the Greens can push Labour even further. In his conference speech on Friday, he argued that electing him as an MP will send a message to the government not to get complacent.
"Vote Green, and watch Labour move," he said. "Voting Green, between general elections, is the most powerful vote you can make. At general elections, the government changes. But between general elections – we change the government."
On recent form it is hard to argue with that. But now Mr Starmer has gone, the Greens argue Labour still faces the same danger from the left, saying Mr Burnham still needs to deliver on his promises. Their own policy offerings include protections against rent rises, immediately bringing water companies into public ownership and de-proscribing Palestine Action.
Mr Polanski has an energetic support base, with activists giving ovation after ovation during his speech. Speaking afterward, Gorton and Denton's Green MP Hannah Spencer told The Mirror that the mood is upbeat.
She said: "It's just unbelievable. When you think back to this time last year, and we were celebrating Zack becoming leader, like this huge boost in members, and members who were really keen and want to get involved, there's just been this shift about people coming and joining the party who realise that there is like a hopeful movement that we're building."
"And when things feel really scary in the world, there is something that we can do to change it. And we've got a lot of wins to celebrate."
If Mr Polanski adds another win on Thursday, it would be a historic upset that would eclipse even Gorton and Denton. Insiders insist it is all to play for, and Green campaigners have been encouraged to miss the conference in order to join a final push in North London. If it does not go well, next year's conference will feel a lot different.
