LESS than a month ago, the polls predicted a crushing defeat for Labour in the Glenrothes by-election, a result that would have spelt the end of Gordon Brown’s premiership.

Now the situation appears to have been reversed, with hopes of a second nationalist by-election triumph in a safe Labour seat looking like a much tougher prospect.

A YouGov poll for The Sunday Times shows approval of Brown’s handling of the credit crisis has propelled his party back into the lead among Scottish voters for Westminster.

In the past seven weeks, Labour has climbed six points to 38%, leapfrogging the SNP, whose popularity has dipped five points to 29%.

If replicated at a general election, it would give Labour a resounding victory — 41 seats compared with seven each for the SNP and the Scottish Liberal Democrats, and the Scottish Conservatives on four.

This means that despite fears Labour was heading for oblivion at the next general election, north of the border the party is only one point down on its performance at the last election.

The biggest losers are the Liberal Democrats, down 12 points on their 2005 level. The SNP insists the financial crisis and looming recession is all down to Brown. The poll — which came as the prime minister broke with precedence by joining the by-election trail in Glenrothes yesterday — suggests his handling of the credit crisis has boosted his party’s popularity.

Despite Brown’s improved ratings, John Curtice, professor of politics at Strathclyde University, believes Labour still has a significant amount of work to do to secure a victory in Glenrothes.

“I do think Brown’s handling of the economy has had an impact on the electorate, but I’m not sure it’s enough. Since July, and the Glasgow East by-election, there’s been a 5.5% swing to Labour. That suggests Glenrothes is going to be extremely tight.

“If Labour can hang onto the seat, it will be seen as a major turning point. If they don’t, this so-called bubble will be well and truly burst. But the SNP remain favourites.”

With 11 days to go until polling, the fall in support for the SNP is a concern to Alex Salmond. Yet, despite the drop in support at Westminster, the nationalists remain by far the most popular party at Holyrood.

As well as leading on the first and second vote, the approval ratings for Salmond remain far higher than for Iain Gray, the Scottish Labour leader. Asked by YouGov who would be best suited to the job of first minister, 38% opted for Salmond, 13% for Gray, 10% for the Scottish Tory leader Annabelle Goldie and 6% for Tavish Scott of the Lib Dems.

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