Tactical voting in just 36 marginal seats can stop a Boris Johnson majority

Anti-Brexit demonstrator outside the Houses of Parliament. Photograph: Jonathan Brady/PA. - Credit: Archant

Fresh polling shows that the Conservative Party’s majority has halved in just two weeks – meaning fewer than 41,000 tactical votes in 36 marginal seats can stop Boris Johnson.

The Best for Britain commissioned polling, carried out by Focaldata earlier this week, found that without tactical voting Labour, Lib Dems, SNP, Greens and Plaid Cymru would hold a combined 286 seats. This scenario would see the Conservative Party win 345 seats and a majority in parliament.

But it is half of the majority predicted by Boris Johnson – and echoed by YouGov’s MRP – a fortnight ago which predicted 366 seats.

It means that pro-EU parties need to win just 36 marginal seats predicted to be won by the Conservatives to prevent a Johnson majority, factoring the DUP could again support the Tories.

Best for Britain have identified the 36 seats where the chances of pro-EU voters successful using their votes tactically to prevent a Conservative victory are highest. According to our data, it would take less than 2,500 tactical votes in these seats to prevent the Conservative Party winning.

The anti-Brexit group now estimates it would take as little as 40,704 pro-EU voters nationally using their vote tactically to prevent a Tory majority.

If tactical voting were successful in just these 36 seats, the Conservatives would win 309 seats, Labour would win 255 seats, Lib Dems would win 14 seats, Greens would win 1 seats, Plaid would win 3 seats, and the SNP would win 49 seats.

The data has been used to inform Best for Britain’s final tactical voting recommendations at getvoting.org with more findings to be announced at a press conference on Monday.

The group adds there are also 73 seats where 5,000 or less tactical votes would prevent the Conservatives winning.

Best for Britain CEO Naomi Smith said: “The Tories will be quaking in their boots today.

“Just a fortnight ago Boris Johnson was on course to win a landslide, but weeks of telling lies and ducking interviews have caught up with him.

“Now he faces the very real possibility of Remainers in just thirty-six marginal seats using tactical voting to cannibalise what’s left of his expected majority.

“This election is on a knife-edge, and if enough Remainers hold their nose and vote for the candidate with the best chance of stopping the Tories in their seat we’re heading for a hung parliament and a final say referendum.”

It follows polling from Gina Miller’s Remain United that suggests tactical voting can stop a Tory majority and create a hung parliament situation.