The Scottish National Party will flood the Glasgow East constituency with close to a thousand party activists today in a final attempt to pull off a stunning by-election victory on Thursday.

The Nationalists believe that on the last weekend of the campaign they can still build up the momentum to overtake Labour and achieve the

22 per cent swing they need to win the seat. If they do, it will fulfil Alex Salmond's promise in the early part of the campaign that his party was set to trigger a “political earthquake”.

SNP sources said yesterday that they would be pulling in activists from all parts of Scotland. “As far as we are concerned, this weekend all roads lead to Glasgow East,” one senior party insider said.

“This could come down to who appears to want to win the most; and getting a lot of what we call ‘body heat' in the constituency sends a message to voters that we want to win the most.”

The strategy is reminiscent of the one employed by the Nationalists on the last weekend of the Glasgow Govan by-election campaign in 1988. The SNP then appeared to be behind Labour with less than a week to go, but intense campaigning on the weekend before polling day led to Jim Sillars, the SNP candidate, pulling ahead of Labour's Bob Gillespie and winning with a 33 per cent swing.

“The last weekend before Govan, it did not look winnable for us. Glasgow East, on the other hand, does look winnable. We had 500 people in the constituency last Saturday and we will have more than that this weekend,” the SNP source said.

However, Labour is also appearing increasingly confident that it can stave off a Nationalist triumph and prevent a repeat of the recent Crewe & Nantwich by-election defeat in England.

Both sides agree on one thing. The outcome will depend on two unknown factors: how successful the SNP is in getting traditional Labour voters to switch directly to vote for their candidate, John Mason, and how successful Labour is in ensuring that that their diehard voters, disenchanted with the Government, can be motivated not to stay at home and instead vote for Margaret Curran, their party's candidate.

For her part Mrs Curran maintained yesterday that, far from being worried about Labour voters switching to the SNP, she was encountering SNP voters who intended to vote Labour. She cited the example of Annie Hall, a pensioner whom she met yesterday in Shettleston Road, who said that while she had supported the SNP in the past she had decided to vote Labour this time.

Mrs Curran said: “I am coming across people who are switching to me. The message I am taking to the constituency is resounding with people.

“They say they want somebody whose first priority is the people of the East End of Glasgow and not someone whose first priority is independence.”

She also expressed anger about how the constituency had been portrayed in parts of the media. “People here resent this area being seen as an area of complete deprivation. It has not been presented as it should be,” she said. Mrs Curran also attacked what she claimed was the decision by the SNP administration in Holyrood to means test a free central heating programme for pensioners.

On the campaign trail yesterday the rising cost of living dominated the minds of candidates and voters alike, after warnings of increases of up to 70 per cent in the price of gas.

The findings, in a report commissioned by Centrica, were seized on by the SNP, who have made rising prices - in particular for fuel - a constant theme in the campaign.

Mr Mason said: “That has been the number one issue on the doorsteps - rising prices of petrol, gas and electricity.

“An SNP victory will send a message to the Prime Minister of the need for action.”

Behind the story: Swings in and out of favour

Could Glasgow East be the new Govan? In 1973 Margo Macdonald. of the SNP. produced one of the biggest by-election shocks in postwar Scottish history when she won Glasgow Govan from Labour with a swing of more than 26per cent. She lost the seat a year later to the man she had beaten - Harry Selby.

Ms Macdonald, who is an independent MSP at Holyrood, was dubbed the Nationalists' “blonde bombshell”. The poll result, on the back of the “It's Scotland's Oil” SNP campaign, appeared to presage a dramatic redrawing of the political map that never materialised.

Jim Sillars, her future husband, produced an even greater swing (33 per cent) in 1988 once again to take the seat in a by-election for the SNP from Labour. It was another false dawn for the Nationalists because Mr Sillars lost the seat in 1992.

The SNP took Glasgow Govan from Labour yet again in the Holyrood elections last year when Nicola Sturgeon, the deputy leader of the party and now Deputy First Minister, won the seat from Gordon Jackson.

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