Gordon Brown
Lord Ashcroft said Labour are set to lose Gordon Brown's home Kirkcaldy and Cowdenbeath seat (Getty)

Labour face deep embarrassment at the general election as the party is set to lose Gordon Brown's current seat to the Scottish National Party (SNP), according to a poll from Lord Ashcroft.

The Tory peer, who questioned 1,000 voters in Kirkcaldy and Cowdenbeath between 19 and 25 February, found a 28.5% swing toward the SNP since 2010.

The data means Kenny Selbie, who is to contest the seat after the former prime minister stands down, will lose out to the SNP's Roger Mullin.

Ashcroft, a former Treasurer of the Tory party, said the Fife seat showed the largest swing to Nicola Sturgeon's party out of the Labour constituencies he analysed in Scotland.

The research also revealed that Scottish Labour leader, Jim Murphy, holds just a one-point lead in East Renfrewshire over the SNP.

Murphy, a former Labour front bencher, said he would defend the seat at the forthcoming general election.

The figures from Ashcroft mean that he will be in for a very tough fight as support from the SNP continues to grow after the Scottish Independence referendum last September.

"As things stand, Labour losses in Scotland could offset their gains from the Tories, leading to something close to a dead heat," Ashcroft said.

"Labour have fallen from their peak above 40% to the low 30s, from which the Conservatives have been unable to break free since the middle of 2012.

"The Liberal Democrats, meanwhile, remain well below half their 2010 vote share, and UKIP have fallen back slightly from their peak at the end of last year."

The study also found that Liberal Democrat grandee Charles Kennedy is predicted to lose his Ross, Skye and Lochaber seat to the SNP after holding the constituency since 1983.

Former Labour chancellor and Better Together spokesman, Alistair Darling, is also estimated to lose his Edinburgh South West to the SNP, according to Ashcroft.

"David Cameron will be rubbing his hands with glee when he sees these polls, because any seat the SNP take from Scottish Labour makes it more likely the Tories will be the largest party across the UK," Murphy said.