The Conservative Party would fall over 40 seats behind Labour in a general election under Boris Johnson, a ComRes poll has found.

The poll, which asked how people would vote under a different Conservative leader, found that 26 percent of voters would vote Tory, behind Labour on 27 percent. The Brexit Party’s support fell to 10 percent, behind the Liberal Democrats on 14 percent.

Using an electoral model, Labour would win the most seats on 285, with the Conservatives on 243 and the Liberal Democrats on 45.

Among Conservative losses would be Amber Rudd, Iain Duncan Smith, Justine Greening, Zac Goldsmith, David Mundell and Maria Caulfield. The party would also lose every seat in Scotland to the SNP.

Among the other parties, the SNP would be on 53, Plaid Cymru unchanged on four, the Greens on one and the Brexit Party on one – gaining Thurrock.

Under the two other potential leaders polled by ComRes, the Conservatives fare even worse.

Should Dominic Rabb become leader, there would be a four point gap with Labour, with 27 percent and 23 percent respectively. Labour would win 306 seats, with the Conservatives falling to 219.

Under Amber Rudd, the gap between the Conservatives and Labour increases to five percent; on 27 percent and 22 percent respectively. The Conservatives would drop to just 204 seats, with Labour on 312 – just 14 seats short of an overall majority. With Rudd as leader, David Cameron’s former seat of Witney would fall to the Liberal Democrats, and the Conservatives would also lose every seat in Wales.