Zack Polanski’s defeat in Holborn and St Pancras last week denied the Greens a parliamentary breakthrough in Keir Starmer’s former constituency. Labour’s Sagal Abdi-Wali held the seat with 45.2% against Polanski’s 32.8% on a turnout of 38.8%.
The comfortable Labour hold gives Prime Minister Andy Burnham breathing space in his effort to revive Labour’s popularity, which plummeted under Starmer and saw many left-wing voters defect to the Greens.
Although the Green leader didn’t win a seat, the substantial support for the party leaves Burnham with a challenge on his left that he cannot afford to ignore.
The result points more to a consolidation of opposition on Labour’s left rather than a fresh wave of defections, since the Greens’ share was only about 3.5 points higher than the combined Green and independent pro-Palestinian vote for Andrew Feinstein in the 2024.
“If this election had taken place a few months ago, when Keir Starmer was Prime Minister and the Greens still at their peak, the result would likely have looked very different,” Luke Tryl, UK Director of More in Common, told The New Arab.
He added that the result signals Burnham is consolidating left voters behind the party again.
Labour responds to the challenge
Burnham has made Labour a tougher proposition for challengers on its progressive flank. YouGov’s pre-election survey of 4–5 October put Labour on 27%, up three points from the previous week, and the Greens on an unchanged 11%.
YouGov also reported in September that 39% of 2024 Green voters would consider Labour, up from 24% in May, which supports the picture of a Labour recovery.
During the campaign, Reuters reported that a number of former Green supporters were receptive to Burnham’s tougher rhetoric towards Israel and closer European ties.
“Burnham may have hurt them pretty badly, but he hasn't put them completely out of the running,” Tim Bale, Professor of Politics at Queen Mary University, told The New Arab.
“There are still a lot of university-educated younger voters and ethnic minority voters who remain deeply suspicious of a Labour government they think has done nothing for them and is insufficiently critical of Trump and the Israeli government.”
For the Greens, Labour’s shift creates a dilemma, as it gives credibility to their claim that voting Green forces Labour to listen, but it may also remove some voters’ incentive to switch party in the first place.
Even Polanski noted this at the party conference, where he told delegates: “Vote Green and watch Labour move.”
Electoral pressure can raise the cost of ignoring progressive voters even before a party wins enough seats to bargain over legislation.
Still, that influence needs to be shown. Green pressure is one plausible factor in Labour’s repositioning, alongside public campaigning, internal party demands, Burnham’s own instincts, and the UK’s response to Israel’s atrocities in Palestine.
“The result backs up what has been seen in the national opinion polls: Labour's support has risen and the Greens' popularity has dipped,” Mitya Pearson, associate professor at the University of Warwick, told The New Arab.
“This does not mean that the Labour Party can now ignore the Greens; clearly there is a group of voters on the left who are willing to defect away from Labour if they don't feel listened to,” she added.
“However, Labour have arrested a lot of the Greens' previous momentum by changing leader.”
Palestine and the limits of Labour policy
The Labour government’s settlement measures in September illustrate both the shift and its limits.
On 8 September, Foreign Secretary Ed Miliband announced plans to ban imports from illegal settlements, act against those facilitating settlement expansion and refuse export licence applications that materially contribute to Israel’s illegal occupation of the West Bank.
He said the legislative package would be in place within six to nine months, alongside immediate sanctions against extremist settlers.
At Labour’s conference on 28 September, Miliband addressed those campaigning for Palestinian rights, saying “you were right”, describing a “reset” in Labour’s approach and referring to “ethnic cleansing by the settler terrorists in the West Bank”.
That marked quite a notable shift in British government rhetoric.
Still, this represents a limited change rather than a comprehensive overhaul of London’s foreign policy.
Indeed, Miliband opposed the wider Boycott, Divestment and Sanctions (BDS) campaign, defended trade with Israel within the Green Line, and reaffirmed Labour’s commitment to a two-state solution, even as settlement expansion continues to undermine its viability, and Israeli officials reject Palestinian statehood.
This is where the Greens’ position remains distinct from Labour’s in attracting pro-Palestine voters. The party demands a full two-way arms embargo, broader sanctions, and an end to military and intelligence cooperation, and reiterated that position following Miliband’s address.
Still, while Labour gained electoral credit for this rhetorical shift, that boost may not last if the policies towards Israel are delayed or narrowly applied, and the Greens can remain poised to scrutinise that gap.
The Greens’ ability to sustain that pressure may now be complicated by their own divisions over the conference motion declaring “Zionism is Racism”. Passed on 4 October by 1,022 to 813, it commits the party to an explicitly anti-Zionist position and a single democratic state across historic Palestine.
Polanski missed the vote while campaigning and has since said he would have opposed it. The chair of Jewish Greens, meanwhile, has called for his resignation, while four of the party’s five MPs publicly opposed the motion.
Combined with criticism from Jewish organisations and the European Green Party’s distancing, the split risks fracturing the broader progressive coalition the Greens need if they are to keep pressuring Labour.
The move would appeal to many pro-Palestine voters. But along with showing divisions within the party, British political analysts suggest the motion had made Polanski and the Greens more polarising across the broader electorate.
It would still be premature to link the motion as the cause of the Holborn defeat. YouGov had already documented weakening Green support before the conference vote, and its effect in this constituency requires evidence from voters rather than assumptions based on timing.
Building influence beyond this election
Repairing internal divisions is only part of the Greens’ task. To rebuild momentum, they also need a domestic programme that gives voters a clear reason to choose them over a recovering Labour Party.
Polanski’s proposed three-year cap on rent increases, set at the lowest of inflation, wage growth or 2%, offers one concrete dividing line. Its credibility will depend on addressing housing supply, enforcement and how tenants benefit in practice.
As More in Common’s Luke Tryl noted, the battle for the left has shifted: unless Polanski can rebuild momentum, Labour now holds the upper hand.
For the Greens, the picture looks promising in some areas. Hannah Spencer’s February victory in Gorton and Denton, with 40.7%, demonstrated that concentrated Green support can win under first-past-the-post.
Targeted campaigns and strong local government remain a more realistic route to influence than hoping to replace Labour nationwide.
Green MPs will have limited formal influence in this parliament given Labour’s majority, said Mitya Pearson, although they could still challenge inner-city Labour seats.
Combined with Labour’s need to unite progressive voters, “this pressure will likely continue to influence the policy decisions the Labour government makes”.
Burnham’s task is to turn renewed expectations into delivery. If Labour follows through on housing, living standards, and Palestinian rights, it may retain voters who previously considered the Greens.
If its promises disappoint, an opening could return, but only if the Greens’ organisation and policy credibility enable them to exploit it.
For now, Polanski’s defeat checks the Greens’ advance and hands Burnham breathing space, even though the vote share suggests the Greens remain competitive in some Labour-held urban seats.
For Palestinians and their supporters, the real test is not the by-election result but whether Labour turns its new language on settlements, arms, and Gaza into concrete action.
If Labour fails to deliver, an opening could re-emerge, but the Greens will need the organisation, unity, and credibility to exploit it.
Jonathan Fenton-Harvey is a journalist and researcher who focuses on conflict, geopolitics, and humanitarian issues in the Middle East and North Africa.
Follow him on Twitter: @jfentonharvey
Edited by Charlie Hoyle