Andy Burnham’s clear-cut victory in Thursday’s parliamentary by-election in Makerfield, Wigan, has paved the way for the former Greater Manchester mayor to launch a bid to replace Keir Starmer as Labour leader.

Under Labour’s rules, only sitting MPs can mount a challenge to the party leader. With Starmer polling at record lows and despised by millions, Burnham is expected to move against him in short order.

He would become Britain’s seventh prime minister in a decade.

Starmer stymied a previous move by Burnham in January to return to Westminster in another by-election. His departure is now a matter of when, not if. While the prime minister declared in advance of Burnham’s victory, and after it, that he was prepared to fight any leadership contest—citing the “mandate” and large parliamentary majority he secured just two years ago—his position is increasingly untenable.

To trigger a leadership election, 81 Labour MPs (20 percent) are required to back a candidate. Almost 100 have already called for Starmer to stand down, with the Guardian reporting Friday that “One MP said they believed there were about 200 Labour MPs prepared – if necessary – to sign Burnham’s nomination papers for a challenge.”

Many MPs, reflecting the position of substantial sections of the ruling class who demand economic stability and not a messy leadership contest that would last all summer, are demanding Starmer walk now, or at least set a timetable for his departure. According to the Times “sources close to the prime minister said he recognises there is growing pressure from the backbenches for him to go” and this weekend he will “consider his position before deciding whether to fight on.”

According to polls, the Makerfield contest would see Burnham neck-and-neck with Nigel Farage’s Reform UK. In May’s local elections, Farage’s far-right party had won every available seat to seize control of Wigan council, which covers the Makerfield constituency, leaving Labour trailing on barely a fifth of the vote.

In the event, however, Burnham was able to exploit both hostility to Starmer in this long-standing Labour stronghold and rally support against the far-right. Campaigning on the vacuous slogans of “change” and “hope,” he secured 24,927 votes—more than half the votes cast (almost 55 percent) and 20 points ahead of Reform’s Robert Kenyon on 15,696 (34.5 percent). Though Reform’s share rose 2.7 points on the last general election, the outcome amounted to a 3.4 point swing from Reform to Labour, handing Burnham a majority of 9,231.

Yet another far-right vehicle, Rupert Lowe’s Restore Britain, took just 3,111 votes but helped lower Reform’s vote. Restore had been talked up as splitting the right-wing vote and denying Reform victory. In the end, however, Burnham comfortably outpolled the combined tally of Reform and Restore.

Burnham’s margin of victory was such that he beat the combined votes of all 13 other candidates, but a major factor was that Liberal Democrat and Green Party supporters voted tactically for Burnham to keep Reform out. The Greens (0.7 percent), the Liberal Democrats (0.4 percent) and the Conservatives (2.2 percent) all lost their deposits; with the Lib Dems share the lowest for a major party in any by-election. The Conservatives’ 2.2 percent was their second-worst by-election result ever, beaten only by February’s Gorton and Denton contest—the seat Burnham had been barred from contesting by Labour’s ruling body of Starmer loyalists.

Burnham’s landslide was, as the WSWS noted earlier, made possible by his good fortune of having spent the past decade in the north of England, away from too-obvious association with Starmer and his pro-war, austerity-enforcing party.

So toxic is the Labour brand—with the ruling party down to 18 percent in national polls—that Burnham’s centred his campaign on the message “Vote Andy for Us.”

Burnham proclaimed himself the candidate of a “new politics,” with his campaign based on “place not party.” As the Telegraph documented, Burnham used the word “Labour” in fewer than 3 percent of his Facebook adverts—just two of them, despite the party spending some £36,000 on 98 posts and videos over the four-week campaign.

The Guardian noted, “By running as a Labour candidate but on a promise to challenge the prime minister, Burnham was able to use the full resources of the governing party while also positioning himself as the option for change. Almost every Labour MP went to campaign at some point over the last few weeks, many more than once. Party officials say they knocked on some doors as many as seven times, managing to speak to 60% of voters during the campaign – far above the normal contact rate.”

This effort, combined with Reform’s own high-profile intervention, produced a turnout of 58.7 percent, exceptionally high for a by-election.

However, despite Burnham’s propensity for “soft-left” rhetoric, including condemnations of social inequality and the “North-South divide”, he is a dyed-in-the-wool Blairite. Prior to his contesting Makerfield, the WSWS explained that whether such a “run-of-the-mill, right-wing social democrat” succeeds or fails, whatever temporary respite he can bring for Labour, will make in the end make no difference to the working class or to the fate of a collapsing Labour Party. Burnham’s elevation to Downing Street and leadership of a pro-war, pro-austerity party will instead lead to an intensification of the assault on the working class.

Indeed, Burnham utilised the by-election to demonstrate to the ruling class his readiness to jettison any faintly reformist statement he has ever made—even ones uttered 24 hours earlier. As the campaign drew to a close, he abandoned his pledge to compensate the WASP women pensioners—born in the 1950s and who have lost thousands of pounds each after not being properly informed of a rise in the state pension age—after the Financial Times pronounced the £10.5 billion bill too costly.

For the ruling class, Burnham’s decisive stance was abandoning his earlier criticism of the bond markets to declare that he would uphold the strict fiscal rules within which Chancellor Rachel Reeves is throttling public spending.

Burnham’s camp leaked as the polls closed that he is now being advised by Andy Haldane, a former Bank of England chief economist; Richard Hughes, a former chair of the Office for Budget Responsibility (OBR); and Jim O’Neill, a crossbench peer and former Treasury minister who worked with George Osborne—the Tory chancellor who enforced savage austerity during the 2010–15 Conservative–Liberal Democrat coalition.

The Financial Times noted, “Hughes was brought in at the start of the month to help prepare Burnham with how his policies would be interpreted by the markets and the watchdog [OBR] should he become the UK’s next prime minister”.

Burnham has presented himself as the antidote to four decades of scorched-earth policies that have left northern towns such as Wigan as de-industrialised wastelands. But such rhetoric was reserved for his campaign videos and social media clips. All such language will be discarded the instant Burnham crosses the threshold of Downing Street.

In an interview with the Times published a week before polling under the headline “Andy Burnham: I’ll cut welfare bill to fund defence,” he declared, “I am not squeamish about saying that the plan would be to reduce the welfare bill. Not at all.”

The Times, which has insisted for two years that Starmer move more quickly to slash welfare and public spending to fund the military war chest, concluded approvingly, “Burnham’s plan is about reducing the benefits bill, and increasing defence spending in the long term.”

Asked by the newspaper whether he agreed with the resigned defence secretary John Healey that the £13.5 billion pledged by the prime minister for the military was insufficient, Burnham answered that “the world has changed” and that “we are going to have to change the assumptions on which we’ve been working,” adding that the priority was “defence and security but also resilience.”