Reform UK has made its first gain of the night with former Tory MP Lee Anderson winning in Ashfield.
Mr Anderson was the deputy Conservative party chairman under Rishi Sunak but was sacked earlier this year following a row over comments he made about London Mayor Sadiq Khan.
He went on to defect to Reform UK, and has now held on to his seat in Nottinghamshire.
Mr Anderson won the seat comfortably, clinching 17,062 votes compared to 11,553 for Labour, who came in second.
In an even further blow to the Conservatives, they came in fourth behind an independent.
Reform UK looks set to establish a foothold in parliament – with Nigel Farage expected to become an MP for the very first time.
Mr Farage hailed “huge” early results after the general election exit poll projected his party would win 13 seats, including in Clacton, Essex, where he is standing.
If correct, that means he will finally enter parliament as an MP, having tried unsuccessfully seven times already.
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Most of the early results were Labour holds in the North East of England.
But in one of the first blows for the Conservative Party, Reform UK came second in nearly all of those seats, pushing the Tories into third place – and even fourth in Gateshead Central & Whickham.
Welcoming the signs of promise for his party, Mr Farage said on X: “It’s midnight, there are two results in from the northeast of England that put Reform on 30% of the vote, that is way more than any possible prediction or projection. It is almost unbelievable.
“And what does it mean? It means we’re going to win seats – many, many seats I think – right now across the country.”
He added: “This is going to be six million votes plus. This folks is huge.”
The clip was captioned: “The revolt against the establishment is under way.”
Mr Farage’s ultimate aim is to make Reform the official opposition to Labour, who are projected to win this election by a landslide.
Sir Keir Starmer’s party looks set to secure the win with an estimated 410 seats – equating to an overall majority of 170 – according to the poll by Ipsos UK for Sky News/BBC/ITV News.
Meanwhile, the Conservatives are projected to win just 131 seats, compared to 365 in the 2019 vote, which could be the party’s lowest seat total in its modern history.
Some of the Tories’ most senior figures are also predicted to lose their seats, including Chancellor Jeremy Hunt, Defence Secretary Grant Shapps and Veterans Minister Johnny Mercer.
The success of Reform is likely to play a huge role in the future direction of the Tory party.
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Speaking to Sky News, former Tory cabinet minister Andrea Leadsom said it was a “devastating night” but claimed the reason for the scale of the projected losses was because they had “not been properly Conservative enough” to win over voters.
She added: “I think Reform have done very well out of it because they’ve been a protest… and we’re going to have to rethink.”
Read more:
What the exit poll forecasts where you live
UK politics is being transformed – here’s how and why
The big Tory beasts who could lose their seats
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However, in a sign of the split that could be to come, former minister and Tory peer Lord Jo Johnson said that the election “raised really important issues as to whether it’s a sensible thing for the Conservatives to try and be Reform-lite and expect that to be a winning political strategy”.
“It doesn’t look to be on the evidence of what we’re seeing today,” he said.