Reform UK’s projected path to No10 could unravel if opposition voters act tactically, new analysis by pollsters suggests.
Research by More in Common shows how tactical voting between Labour, Liberal Democrat and Green supporters could potentially cost Reform dozens of seats.
The findings follow the Caerphilly by-election last October where there were believed to be signs of tactical voting in action, with Plaid Cymru’s Lindsay Whittle winning over thousands of ex-Labour supporters to see off Reform UK by 3,848 votes.
If just 20 per cent of Labour, Liberal Democrat or Green voters, in constituencies where their preferred party is less likely to win, cast their ballots strategically for the strongest opposition candidate, Reform UK could lose its parliamentary majority.
In contrast, tactical voting between Conservative and Reform supporters would primarily benefit Reform, though the effect is less significant overall.
According to More in Common's analysis, if one in five Tory or Reform supporters intending to vote for the smaller of the two in their constituency voted for the other, the Conservatives could win a further six seats and Reform another 22.
Director of the organisation, Luke Tryl, said: "The threat of tactical voting, combined with the narrow margin of many of Reform’s projected victories, suggests their momentum may have at least temporarily stalled.
"That, combined with the fact we are still years from an election, means that despite their success in 2025, the path to the next general election is still far from known."
Tactical voting could potentially cost Reform dozens of seats
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Scarlett Maguire, founder of Merlin Strategy, said Mr Farage "should be worried about the implications" if tactical voting is to occur in the next General Election.
She told GB News: "The Senedd by-election in Caerphilly clearly shows that there is a substantial appetite for progressive tactical voting to stop Reform, and Nigel Farage should be worried about the implications of that if replicated across the UK.
“However, there are some caveats. Firstly, it will be harder to rally a progressive tactical vote behind an unpopular Government and a Prime Minister as disliked as Keir Starmer is by those on the left and the right.
“Secondly, if the election boils down to a head-to-head between Keir Starmer and Nigel Farage, we could also expect some sort of tactical vote on the right - although not all Conservatives would stomach this.
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A polling guru said Nigel Farage 'should be worried about the implications' of potential tactical voting
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“Finally, and potentially most importantly, with the polls now a five-way fight, it is going to be very hard to work out who is best to defeat Reform in each constituency.
“This could make the practicalities of tactical voting much messier than many at the moment are anticipating."
Putting aside the possible threat of tactical voting, Reform UK is on course for a three-figure majority in the House of Commons while Labour is set for a huge slump, polling by More in Common found.
The organisation suggests, based on polling of more than 16,000 Britons, Reform would take 381 seats if a General Election were held today.
Polling shows Reform is projected to win 381 seats if a General Election were held today
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Mr Farage's party is projected to win a majority of 112 over all other parties combined, with their earlier rapid polling gains now seemingly holding steady.
This would see Reform winning 60 per cent of seats on 31 per cent of the vote, rivalling the 2024 General Election as one of the most disproportionate results in modern British history.
However, Sir Keir Starmer and the Labour Party's slump is projected to continue.
On a local level, Labour ended 2025 with 89 seats fewer than they started.
The poll suggests Sir Keir's party would slump to just 85 seats, a loss of 326 seats from their July 2024 landslide.