As many as two-thirds of the seats the Tories lost yesterday was the result of Reform UK splitting the Right-leaning vote, analysis revealed last night.
In more than 170 of the 251 constituencies lost by the Conservatives, the Reform vote was greater than the margin of the Tories' defeat.
This was the case in seats across the country, particularly in so-called 'Red Wall' constituencies snatched from Labour by former Tory prime minister Boris Johnson in 2019.
The analysis, by polling guru Professor Sir John Curtice, lays bare the scale of the damage caused by Nigel Farage's insurgent party after it racked up more than 4million votes, or 14.3 per cent of the national vote share.
It shows that former prime minister Rishi Sunak's repeated warnings that a vote for Reform was a vote to hand Labour a huge majority and a 'blank cheque' – a sentiment echoed by this newspaper this week – were correct.
Reform snatched more Conservative seats than expected. Pictured: Party leader Nigel Farage, pictured at a rally on Thursday
Richard Tice, pictured with Mr Farage, who overturned a 27,402 Tory majority to win Boston and Skegness making him one of a handful of Reform MPs
But Mr Farage yesterday dismissed the idea he was single-handedly responsible for handing Labour a thumping majority.
At a press conference in Westminster, he said: 'The truth is, the Conservatives sunk themselves by betraying the 2019 [general election] vote.
'It's just as simple as that. They've done this to themselves and there are large parts of the country – the Red Wall in particular – where it's the Conservatives that are splitting the Reform vote because we are now the challengers to Labour in those constituencies.'
Reform finished in second place in 98 seats.
However, in one particularly stark example of how it split the Right-leaning vote, Labour won Poole with 14,168 votes compared with the Tories' 14,150.
But Reform hoovered up 7,429 of Right-leaning votes to finish third. Just a fraction of these voting Conservative would have kept Labour out.
It was a similar story in South Dorset, where Labour won with 15,659 votes to the Tories' 14,611. Reform won 8,168 to finish third. Labour also won in Rother Valley with 16,023 votes, compared with 15,025 for the Tories.
The prime minister Rishi Sunak's delivering his leaving speech outside No 10 with his wife Akshata Murty
Reform finished third with 7,679, again more than making up for the margin of the Tories' defeat.
Sir John said: 'Of course, not everybody who voted Reform would have otherwise voted Conservative. But they most certainly voted Conservative in 2019.
'These statistics underline the extent to which the heavy loss of Conservative votes to Reform has cost Sunak's party dear.'
Lower turnout among former Tory voters also had an impact.
In the 2019 election, Mr Farage was leader of the Brexit Party, which has now morphed into Reform.
But he cut a deal with Mr Johnson to stand down candidates in 317 seats won by the Tories at the previous election to give the Conservatives a better chance of winning and to deliver Brexit.
However, Mr Sunak did not seek a deal with Mr Farage in this election, which some Tories believe was a strategic mistake.
Mr Farage made the shock decision to stand two weeks into the race.
Pressed on whether he was responsible for helping deliver a new Labour PM who wants to grant asylum to illegal arrivals, Mr Farage said: 'Well, we've just got rid of a PM who let 50,000 illegal migrants cross the English Channel.'