Zack Polanski’s failure to win the Holborn and St Pancras by-election is not just a disappointment; it undermines the Green party leader’s entire strategy for his party and will inevitably bring his leadership into question. In a few months, Polanski has gone from being just about the most successful party leader of the moment to being the one who is surely now in greatest trouble.
The entire point of Polanski’s tilting away from environmental issues towards Palestine was to exploit anger at what left-wing and Muslim voters perceive to be Labour’s soft attitude towards Israeli leader Benjamin Netanyahu and his war on Gaza. It was always going to run the risk of offending the lentil and sandal vote, the party’s terribly nice middle class voters.
It’s true that the Green party’s share of the vote was up considerably on 2024: the Greens got 33 per cent of the votes, up 22 points on two years ago. But Polanski still fell more than 3,000 votes behind Labour’s winner Sagal Abdi-Wali.
Polanski has gone from being just about the most successful party leader of the moment to being the one who is surely now in greatest trouble
Holborn and St Pancras is exactly the sort of constituency where the Green party’s new strategy might have been expected to work. In the 2021 Census, 21 per cent of the constituency’s population were Muslim, more than three times the national average. In the 2024 general election, Keir Starmer had a strong challenge from left-wing independent Andrew Feinstein, a former supporter of Jeremy Corbyn, who campaigned heavily on Gaza. While Starmer was not in danger of losing, his share of the vote fell by 17 per cent, and Feinstein came second. Many Greens wanted Feinstein to be the party’s candidate in the by election, before Polanski pulled rank and decided to stand himself. Surely, the chance to get the Greens’ leader into Parliament would stir environmentally-conscious North Londoners.
Polanski couldn’t have got it more wrong. Even the Greens’ performative conference motion declaring that ‘Zionism is racism’ could not swing he seat in the party’s favour. The Greens’ surge in late 2025 and early 2026, which culminated in victory in the Gorton and Denton by-election, is now starting to look as if it was no more than a personal protest against Starmer on the part of dissident Labour voters. With Starmer now out of the picture there is little to drive people towards the Greens. The Burnham bounce, which at first looked as invigorating as an overweight Dad on a child’s trampoline, just got a whole lot bouncier.
While Polanski is, naturally, the biggest loser from the by-election, the result serves as a warning to Conservatives and Reform UK. Although British politics has atomised into a five party system, it has become increasingly evident in recent months that the Left has become rather more inclined to vote tactically than is the Right. That matters hugely, because in the next election we could end up with seat after seat falling to a left-wing candidate as the right-wing vote is split between the Conservatives and Reform UK.
Even more worrying for the latter two, it now looks as if we might, after all, be retreating to being a four party system, with the Greens’ efforts to become a nationwide party faltering. It is hard at the moment to see them advancing beyond the few strongholds which they currently hold. If you are a left-leaning tactical voter, all roads currently point towards the Labour party. Unlike Starmer, Burnham is looking capable of keeping the party in power after 2029. And the more he looks able to do just that, the more the left-wing vote will surely coalesce around him.
Things could change. A full-on fiscal crisis, leading the government to seek a bailout or supercharging inflation by trying to print its way of debt, could turn the whole political picture upside down. But for now, Holborn and St Pancras has made a Burnham general election victory look all too probable.
