Andy Burnham said support for him would be a “vote to change Labour” as he launched his campaign to return to Westminster and potentially challenge Sir Keir Starmer for the keys to No 10.
The Greater Manchester mayor, who is seeking to win the Makerfield seat, said Labour “need to be better than we have been” and promised to give voters “the party back they used to know”.
Allies of Mr Burnham have suggested he may not launch a bid for the party leadership immediately if he is successful in his attempt to return to Parliament in the June 18 contest.
But he is widely viewed as Sir Keir’s main rival for the top job if he wins the by-election.
Under Sir Keir, Labour suffered a devastating series of setbacks in elections in England, Wales and Scotland earlier in May, triggering a wave of speculation around the Prime Minister’s position.
In an apparent criticism of Sir Keir’s leadership, Mr Burnham said: “I know my own party needs to change. We need to be better than we have been.
“A vote for me in this by-election is a vote to change Labour.”
He said the voters of Makerfield would get “the party back they used to know”.
He promised he was not offering “more of the same”.
“This is a change by-election. Politics in this country, British politics, is tired,” he said at his launch event in Ashton-in-Makerfield.
“It needs a new script and over the next four weeks the people of Makerfield are going to write that script, and it’s great that they’re going to get that chance.”
Speaking to reporters after his speech, Mr Burnham – a supporter of electoral reform – said he wants to see Labour’s next manifesto commit to introducing proportional representation.
But he ruled out changing the system before the next election, saying: “I think you’ve got to honour manifestos.”
He went on to say there is “space to be more radical” within Labour’s 2024 manifesto, including building more council houses and with rail renationalisation, and he backed reform of council tax.
He said: “It’s a highly regressive tax, and I think it’s not justifiable based on those 1991 valuations. I see a big case for land and property and business taxation to be changed.”
Mr Burnham’s campaign launch was attended by several Labour backbenchers and his close friend Liverpool City Region Mayor Steve Rotheram, as well as the party’s Chief Whip, Jonathan Reynolds.
Pollsters have signalled that having Mr Burnham running will significantly boost Labour’s chances of retaining the seat, but it could still prove a tough contest against Nigel Farage’s Reform UK.
Josh Simons, the Labour MP who stood down to make way for Mr Burnham, won in 2024 by just 5,399 votes while Reform comfortably won every ward in the constituency at this month’s local elections.
Meanwhile, the Liberal Democrats unveiled Stockport councillor Jake Austin as their candidate to contest the seat.
Mr Austin said the people of Makerfield “deserve so much more than the failing Labour Government or the divisive politics of Reform UK”.
On Thursday, the Green Party announced that its candidate, Chris Kennedy, had withdrawn from the race just hours after he had been selected.
The party said Mr Kennedy had withdrawn for “personal and family reasons”, but it later emerged that he had shared posts on social media claiming an attack on Jewish ambulances in north London had been a “false flag” operation.
A Green spokesperson said Mr Kennedy had deleted and apologised for the posts, but added the party stood by its previous statement about the reasons for his withdrawal.
I went out in the van with Cllr Rob Kenyon. This is his story. pic.twitter.com/UTGPZdzx4p
Reform’s Robert Kenyon – a plumber who said he is “ready to take on the King of the North” in a reference to Mr Burnham’s nickname – posted a video on social media with Mr Farage travelling as a passenger in his van.
He said: “For me, Makerfield isn’t a stepping stone, it’s my home. The people here are my neighbours, friends and family.”
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