Southport has a Labour MP for the first time since the constituency was created in the 1880s.
Merseyside’s sole Conservative MP Damien Moore, who has represented the seaside town since 2017, was dramatically ousted by Patrick Hurley.
Labour achieved a swing of 13.2% from the Tories, whose hopes were in large part dashed by the rise of Reform UK.
Southport had only ever been represented by the Conservatives and Liberal Democrats.
Mr Hurley took 17,252 votes to Mr Moore’s 11,463, with Reform’s Andrew Lynn in third place with 7,395.
Earlier, Mr Moore conceded that he expected to come a “respectable second” and suggested his party had failed to reassure voters about illegal migration.
He told the BBC: “Many of those who voted for me in the past say they’ve liked me personally – but they think the real main plank was the lack of leadership on the issue of illegal immigration.”
Mr Moore had enjoyed a near 7,000 vote majority after the 2019 election, in which Reform UK, then called the Brexit Party, did not field a candidate.
Mr Hurley, speaking after he was announced as the winner, told the BBC: “I feel relieved the campaign is over; I am eager to get working.
“The town has seen better days, if you walk down Lord Street it looks tired.
“People have been mentioning the pier being closed to me on the doorstep and everywhere looks like it’s seen better days and needs investment.
“Southport’s always had pockets of deprivation, but under the Tory government those pockets have expanded.”
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