A YouGov poll for The Times found 31 per cent of voters would be more in favour backing independence if Theresa May was returned to 10 Downing Street after tomorrow’s election.
The findings include 15 per cent of No voters from the 2014 referendum, when 55 per cent were against independence.
If these voters switched to the Yes camp they would give First Minister Nicola Sturgeon the votes required to take Scotland out of the UK in a second referendum.
Labour voters were the most likely to move from the unionist side.
The research comes after Nicola Sturgeon claimed Kezia Dugdale had promised that Labour would not stand in the way of a second referendum during a private conversation last year, during last night’s TV debate.
The SNP leader said a referendum would give Scotland a “choice” between independence and a hard Brexit.
Ms Sturgeon: “You [Dugdale] used to agree with me on that. You and I spoke the day after the EU referendum and you told me then that you thought the change with Brexit meant that Labour should stop opposing a referendum.”
The claim made less than 36 hours before voters go to the polls for the General Election on Thursday, was disputed by Labour and Ms Dugdale who called the claim a “categoric lie”
The Scottish labour leader said: “The idea that I would do anything other than protect the United Kingdom is absolute nonsense.”