The Green Party has won the Gorton and Denton by-election, with Hannah Spencer taking the seat from Labour in the Greens' first ever Westminster by-election victory.

Labour, which took the Greater Manchester seat with more than 50% of the vote in 2024, was pushed into third place behind Reform UK - a result which will increase the pressure on Sir Keir Starmer's leadership.

In an emotional acceptance speech, local plumber Spencer promised her supporters that "earning your trust starts now" as she celebrated a majority of more than 4,000.

This is the second by-election since Labour's general election victory in 2024 and the party's second loss to a party with only a handful of sitting MPs.

The poll was triggered by the resignation of former Labour health minister Andrew Gwynne, who was suspending from the parliamentary party for offensive WhatsApp messages a year ago.

The Greens' victory at Gorton and Denton represents the sixth largest Labour majority to be overturned at a by-election since World War Two, in a seat that had been held by the party for more than 100 years.

Spencer received 14,980 votes, nearly 41% of all votes cast, and there was a swing of 26.4% from Labour to Greens.

Reform UK's Matt Goodwin came second with 10,578, while Labour's Angeliki Stogia was third with 9,364. The Conservative's Charlotte Cadden came fourth with 706 votes - the party's worst ever by-election result - and the Liberal Democrats' Jackie Pearcey had 653. No other parties got more than 200 votes.

In her victory speech Spencer - who becomes the Green Party's fifth MP - said she would "fight" for those who had been "left behind".

People have voted for "someone like me, who is actually just pretty normal", the 34-year-old said, adding: "All we have done is... listen to people."

Spencer, who is also a councillor and leader of the Green Party group on Trafford Council, said that for too many in the constituency "a nice life" was no longer possible, with people instead "working to line the pockets of billionaires".

She went on to promise to stand up for "my Muslim friends" as well as the "white, working class communities", before apologising to her plumbing customers for needing to cancel jobs now she is an MP.

Green leader Zack Polanski told BBC Breakfast Gorton and Denton was only his party's 127th target seat and the victory showed "there's no no-go areas for the Green Party".

Reform UK's Goodwin said he thought he had "embarrassed Labour in one of their strongest seats".

"I think if we can do this here, we can do this pretty much anywhere," he added.

Blaming the Green victory on a "coalition of Islamists and woke progressives", Goodwin said: "I think what you've seen is the emergence of a dangerous sectarianism in British politics. I think the Greens are riding a very dangerous wave."

Transport Secretary Heidi Alexander said the result was "disappointing" but people "should not read too much" into it, arguing that "different dynamics" were at play during a general election.

She told BBC Breakfast the public were not yet feeling the positive impact of the government's long-term decisions, which "was a hard message for us to land".

Last month Greater Manchester mayor Andy Burnham, a potential leadership challenger to Sir Keir, was blocked from standing in the seat by Labour's ruling National Executive Committee.

The move was backed by the prime minister but some Labour MPs, including Karl Turner, said he would have been the party's best chance of winning the seat.

Turner told BBC Radio 4's Today programme the result was "catastrophic" for Labour, blaming "unpopular" policies.

Labour MP Richard Burgon said Sir Keir had put "factional interests over having the candidate best placed to win".

He called for Labour to "stop treating progressive voters with contempt - and start appealing to them".

Labour's deputy leader Lucy Powell, who voted for Burnham to be allowed to stand, was asked whether Labour would have won with him as the candidate.

"That's a different discussion for a different day," she told the BBC. "Had he won this seat we would've been facing a [mayoral] by-election across Greater Manchester as well."

She added: "We do need to change how we operate, the prime minister has made that clear over recent weeks."

The result piles further pressure on Sir Keir ahead of crucial May elections in Scotland, Wales and some English councils.

Sharon Graham, leader of the Unite, Labour's biggest trade union backer, said the party needed to "ditch the gimmicks and get back to being Labour".

"Workers and families are hurting. We have a cost of living crisis largely being ignored and investment in jobs for the here and now being blocked by a Treasury that doesn't seem to understand the basics of what is needed to build Britain," she said.

"Stop listening your rich mates and start listening to everyday people."

Meanwhile, an election observer group raised concerns about family voting in the by-election, an illegal practice where two voters use one polling booth and potentially direct each other on which candidate to choose.

Democracy Volunteers said it witnessed the practice in 68% of polling stations it observed - the highest levels at any election in its 10-year history.

Reform UK leader Nigel Farage said this raised questions "about the integrity of the democratic process in predominantly Muslim areas", claiming the election was "a victory for sectarian voting and cheating".

Manchester City Council said no issues had been reported and it was disappointed Democracy Volunteers had waited until after the close of polls to make the claims.

Polanski said if any wrongdoing had happened there should be an investigation, but pointed to the council's statement denying any issues.

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