The upcoming by-election in Holborn and St Pancras is being viewed by Labour strategists as a crucial indicator of whether Prime Minister Andy Burnham may call an early general election. The by-election, expected to take place on October 8, follows the departure of Sir Keir Starmer from Parliament after he was ousted as both prime minister and Labour leader earlier this month.

Labour sources say the contest will provide a test of whether the party, under Burnham’s leadership, has managed to diminish the rising challenge from the Green Party. The Greens have been gaining support in some traditional Labour strongholds, highlighted by Hannah Spencer’s third-place finish ahead of Labour in the Gorton and Denton by-election earlier this year.

For the Holborn and St Pancras seat, Labour has selected Camden Council leader Sagal Abdi-Wali, a former child refugee to the UK, as its candidate. The Greens, meanwhile, have fielded party leader Zack Polanski, marking a high-profile challenge in this north London constituency. Labour insiders suggest that a strong showing against Polanski would signal that the party is regaining lost ground on the left.

One source emphasized that Polanski’s candidacy turns the by-election into an opportunity for Burnham to assess the strength of the Green threat: “Because Keir’s seat was a target and Polanski is running in it, this gives the PM a perfect opportunity to see if the Green threat has gone with a change of leader.” The source added that Labour had seen a notable number of defections to the Greens under Starmer’s leadership but that trend may now be reversing.

Some officials also noted that Labour’s recent decision to sanction Israeli settlers and adopt a firmer stance toward the government of Benjamin Netanyahu might have weakened Green Party appeal among left-leaning voters—an element that will be examined at the by-election.

There is speculation that Burnham could call a snap general election as early as November, which would be unusually soon after the October by-election. However, Downing Street officials have publicly dismissed such claims. Burnham himself told the BBC in early September that he would not seek an early election, stating: “I’m going to rule it out... I don’t think people want it.” A Number 10 source reiterated that an early election is “complete nonsense,” with the prime minister having “ruled it out.”

Despite these denials, some political observers suggest that Burnham faces difficult policy decisions on taxation and public spending without a fresh electoral mandate, as he remains bound by Starmer’s manifesto platform. Polling experts, including Sir John Curtice, warn that Labour’s current polling advantage is insufficient to guarantee a broad majority, cautioning against an early poll.

Still, government and opposition preparations have already begun. Whitehall sources have reported that civil servants are undergoing training for a possible period without a sitting government, a standard procedure ahead of a general election. Opposition parties appear to be preparing as well, with the Reform Party announcing a £72 million donation from two crypto billionaires intended for an election campaign fund. Conservative leader Kemi Badenoch has also requested a briefing on government finances in anticipation of a potential poll.

As the by-election approaches, all eyes will be on Holborn and St Pancras to gauge the Labour leadership’s prospects and the broader political landscape ahead.