NewsPoliticsAndy BurnhamSeismic decisions loom for Labour as Andy Burnham secures a return to Westminster with a convincing by-election win that could spell the end of Keir Starmer's premiership07:43, 19 Jun 2026Updated 08:00, 19 Jun 2026It wasn’t even close. Andy Burnham stormed to victory in Makerfield, winning the seat with a majority of more than 9,000 votes. He nearly doubled Labour’s majority and relegated Reform to a distant second.‌For all the talk about Rupert Lowe’s far-right Restore party being decisive in squashing Reform’s vote, Burnham got more votes than all his opponents combined.‌This convincing win gives the now former Mayor of Greater Manchester two things. A return to the Commons where he can challenge Keir Starmer for the leadership. And proof to the world - and to Labour MPs - that his plan can work.‌Makerfield has long been a Labour stronghold but Reform seized control in the wards up for election in last month’s local council contests. It was not easy for Labour to win here, especially against the backdrop of the Government and the PM’s tanking poll ratings.But Burnham’s win - particularly the size of the majority - will give him to chance to say that that he can beat Reform everywhere, as he has in Makerfield. When his bid for the keys to No10 comes, expect this to be a core part of his argument.‌Sceptics will point to the fact that a by-election is not a general election. Burnham’s popularity in Greater Manchester will have been on his side - and there’s no evidence he could repeat this in say, Grimsby or Great Yarmouth.But Labour MPs, ground down by the negativity towards Keir Starmer and the Government on the doorstep, will feel a glimmer of hope this morning. Not only were Reform walloped, but Burnham was able to appeal to progressive voters as the best chance to keep out Nigel Farage.The Prime Minister remains defiant - and will be out and about today, showing he’s getting on with the job of governing the country. He sees the general election win as a personal mandate, and is said to be privately furious with how Burnham has conducted himself.‌Behind the scenes, work is underway to prepare to fight a leadership challenge. Allies have been sounding out donors, and drawing up a team to run Starmer’s campaign.Ahead of the results, a No10 source told me: “We don’t think there should be a leadership challenge, either for the party or the country. All the key indicators are starting to move in the right direction. But if there is a challenge, of course he’ll be ready to fight it.”The source added: “We are getting on with governing but we need to be ready to go on day one. We need the money, we need the team. We hope that’s not needed. But we have to be ready to go if it is.”‌But the threat to his authority is grave now - and the next few days could be seismic. Burnham's camp are keen to avoid a potentially bitter and divisive leadership contest, and want the PM to agree a timetable to go. But Starmer is unlikely to agree to this unless his hand is forced by his Cabinet and his MPs.Then there's Wes Streeting, who resigned as Health Secretary last month and wants to run for the top job. And there's always the prospect of a dark horse candidate emerging from the shadows.It's not just Labour that has some soul-searching to do. Reform has lost a second by-election that they’ve thrown the kitchen sink at winning.Article continues belowThey were defeated by the Greens in Gorton and Denton in February, and now Labour has walloped them in Makerfield. Farage’s wild claims that he’s going to be PM don’t seem quite so solid now.Lizzy BuchanLizzy Buchan is the Mirror's Political Editor, overseeing a team in Parliament that covers all the action in Westminster and across the country, focusing on the stories that matter to Mirror readers. She has covered politics since 2017, joining the Mirror in 2020 from The Independent. She previously reported on Parliament for the Press Association, and covered health and news for The Scotsman, the Edinburgh Evening News and Cambridge News. Choose Daily Mirror as a 'Preferred Source' on Google News for quick access to the news you value.‌Rupert LoweAndy BurnhamLabour PartyPolitics