FTI Consulting UK Public Affairs Snapshot: Burnham sweeps Makerfield and sets sights on Number 10.

Andy Burnham has swept to a decisive victory in the Makerfield by-election and will now return to Parliament after almost a decade away from Westminster. The result is a significant moment in British politics: a sitting Mayor using a by-election as a springboard to challenge the incumbent Prime Minister. With Burnham having proved – comprehensively – that he can successfully take on Reform UK, his ascendancy appears almost inevitable. Yet with Keir Starmer digging in and pledging to contest any leadership challenge, the route from Makerfield to Number 10 remains uncertain.   

In a result that exceeded pollsters’ predictions, Burnham secured 55% of the vote, comfortably ahead of Reform UK’s Robert Kenyon on 35%. Restore Britain, the breakaway party founded by Rupert Lowe, took 7%, but Burnham outpolled the combined vote share of every right-wing challenger in the race.  

The backdrop of this result is significant. Little over a month ago, Reform UK decisively won 24 of the 25 local council seats in this area and the party continues to enjoy a comfortable lead over Labour in national polling. On paper, Makerfield – a broadly white working-class constituency where Labour has been struggling to retain support – was theirs for the taking. 

Instead, Burnham delivered a decisive victory. He increased Labour’s vote share by almost 10 percentage points on the 2024 General Election and, in doing so, has reinforced his reputation as the party’s strongest asset in defeating Reform UK. Burnham won in Makerfield not despite being a Labour politician, but by making the case that, under his leadership, Labour’s proposition to the country would be different.  

For Reform UK, the result is a disappointing one, raising questions over its candidate selection process and how they can address the threat of Restore Britain on their right flank. But today, the story is all Burnham.  

The scale and the context of the result make it difficult to dispute that he has a personal mandate to reverse Labour’s fortunes nationally. His strong personal brand on the campaign trail was in stark contrast to a Prime Minister perceived as lacking in charisma. Standing in Makerfield was a huge risk, not only for Burnham’s own political future, but for the Labour Party more broadly. It is a gamble from which Burnham looks set to reap significant rewards.  

Despite his victory today, the mechanism through which Burnham might reach Number 10 remains uncertain. The Prime Minister has continued to insist that he will not “walk away” should Burnham mount a leadership challenge. However, the pair are expected to meet in the next few days, with discussions likely to focus on whether a “managed” transition of leadership can be agreed. 

The scale of Burnham’s victory will only increase pressure for a negotiated departure timetable. Many within Labour now view a full- blown leadership contest, which would likely take at least two months, as both unnecessary and damaging.  

If Starmer holds his nerve, pressure will intensify. Cabinet ministers sympathetic to Burnham could resign – potentially as soon as early next week – in an attempt to force the Prime Minister’s hand.  

For Starmer, the most orderly route may be to set out a timetable for his departure and facilitate a smooth transition of power. It is this scenario that is increasingly viewed as the most likely outcome, albeit one that may be prompted by those around Starmer’s Cabinet table rather than the Prime Minister himself. 

Former Health Secretary Wes Streeting previously indicated that he had the support from within the Parliamentary Labour Party to launch a leadership challenge. The prospect of Streeting triggering a contest now seems unlikely.  

A Burnham Government? 

Regardless of what happens next, the new MP for Makerfield will now be expected to answer the thorny national questions which he sought to avoid during the election campaign.  

Burnham’s leadership pitch is built around “Manchesterism” – shifting power away from Westminster and towards local communities. Alongside this, he has committed to greater state control of utilities under a model of “business-friendly socialism”.   

Yet the shape of a Burnham administration remains unclear, and his political flexibility to date leaves a number of questions unanswered. In September 2025, Burnham argued that Britain should not be “in hock” to the bond markets. More recently, he has pledged to abide by Rachel Reeves’ fiscal rules and honour Labour’s commitment not to raise taxes. Which version of Burnham may ultimately arrive in Downing Street remains an open question.  

Markets were down following this morning’s result. Until further details on timings, the contours of Burnham’s economic programme, and crucially, his choice of Chancellor, become clearer, a degree of volatility is likely to persist. 

 Ultimately, however, a Prime Minister Burnham would be boxed in by the same structural constraints that left Starmer and Reeves with limited room for manoeuvre: an unproductive economy, unresolved demands for increased defence spending, and a significant crisis of young people not in work or education. The list could go on.  

In difficult fiscal circumstances, and with the Autumn Budget looming closer, Burnham will require significant creativity to address those issues without expending substantial political capital. Indeed, when he becomes the face of the very establishment politics he was protesting, sustaining momentum will be a far more difficult proposition.