Report by ITV Granada Reports political correspondent Lise McNally
West Lancashire's newest MP has told the Conservatives it is time to "move out of the way".
Ashley Dalton comfortably won the by-election for Labour - making it the Conservatives third North West loss in as many months.
She demanded a general election, telling Prime Minister Rishi Sunak it was time for Labour to take over.
Ms Dalton, who works part-time for a local charity, secured a majority of 8,326 over Conservative candidate Mike Prendergast, with a 10.52% swing from the Tories to Labour.
Bitterly cold conditions on polling day and the expectation of an easy Labour hold contributed to turnout of less than 32%.
The by-election was triggered after Rosie Cooper stood down after 17 years in November following her appointment as Chair of Mersey Care NHS Foundation Trust.
Speaking after the landslide result Ms Dalton said: "It is a huge honour to be elected the Member of Parliament for West Lancashire.
"Lancashire is the place I grew up and I am proud to still call it home today."
She added: "It's the beginning of something really exciting and to have people across West Lancashire put their faith in me to represent them in parliament is a real honour""My first priorities are to tackle the things that really matter to people in West Lancashire, and that's the Ormskirk A&E, which is a direct result of underfunding in our NHS, and public transport in the roads around the area, and that's a direct result link to the underinvestment in our public transport.
"But also those things that really matter to people is the cost of living - that's something we need to be holding the Government to account for, and demanding that they do a lot more for working people."This is the worst vote for the Conservatives in this seat, ever. An 11% swing to Labour. and I think what it shows us is that people are not willing to get behind the Conservative party.
"They don't believe that Rishi Sunak has got a mandate to govern, and what they do believe is that there is hope and optimism in the Labour Party, and they're putting their weight behind that."
Sir Keir Starmer sent his congratulations to Labour’s Ashley Dalton, who enjoyed a comfortable win in the West Lancashire by-election in the early hours of Friday morning.
“Ashley, I look forward to working with you,” the party leader said.
“The message from West Lancashire today is clear - after 13 years of Tory decline, it’s time for a Labour government.”
Rachel Reeves also welcomed Labour’s newest MP Ashley Dalton, calling her by-election win a “really great result” in West Lancashire.
The shadow chancellor, speaking during a visit in Bolton, pointed to a “strong swing, double-digit swing, to the Labour Party”.
“Voters there are sending a clear message to Rishi Sunak and his Government that frankly they are no longer fit to govern and people want a general election and a choice now about who is in government because this Government have run out of ideas and they’ve run out of road,” the Labour MP said.
In a statement announcing her intention to stand down, Ms Cooper, 72, said she had done a "considerable period of soul searching", adding that recent events had "taken their toll", after threats were made against her life.
Jack Renshaw is serving a life sentence for plotting to murder Ms Cooper in 2017 and a police officer who was investigating him for child sex offences.
Six candidates had put themselves forward to succeed her.
Ms Cooper first became MP in 2005, securing more than 52% of the vote. In the 2019 election she had a majority of 8,336 - a drop from 2017.
The constituency has been a Labour stronghold since 1992, where Colin Pickthall took the seat from Conservative Ken Hind, who had held it since 1983.
It is the first time the Tory vote has dipped below 30% since the 1997 general election, which Tony Blair’s Labour party won by a landslide.
Reform UK secured 997 votes, ahead of the Liberal Democrats on 91, the Greens with 646 and the Official Monster Raving Loony Party with 210.
Full results from West Lancashire by-election
Turnout: 22,581 (31.27, -40.53%)
Labour majority: 8,326 (36.87%)
Conservative to Labour swing: 10.52%
Ashley Dalton (Labour) 14,068 (62.30%, +10.16%)
Mike Prendergast (Conservative) 5,742 (25.43%, -10.88%)
Jonathan Kay (Reform UK) 997 (4.42%)
Jo Barton (Liberal Democrat) 918 (4.07%, -0.80%)
Peter Cranie (Green) 646 (2.86%, +0.49%)
Howling Laud Hope (Official Monster Raving Loony Party) 210 (0.93%)
Compared to 2019
2019: Lab maj 8,336 (15.83%) – Turnout 52,663 (71.80%)
Cooper (Lab) 27,458 (52.14%); Gilmore (C) 19,122 (36.31%); Thomson(LD) 2,560 (4.86%); Stanton (Brexit) 2,275 (4.32%); Puddifer (Green)1,248 (2.37%)
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