SNP set to sweep Scotland, but what next?

EDINBURGH/GLASGOW, May 6 (Reuters) - With Scottish nationalists set to crush their opponents north of the border, their role in Britain's future political landscape was being fiercely argued on Wednesday on the eve of the United Kingdom's parliamentary election.

Prime Minister David Cameron made a rare visit to Scotland to warn of what he saw as the dangers posed by the pro-independence Scottish National Party.

His partner in the ruling coalition, Liberal Democrat leader Nick Clegg, also travelled north in what appeared to be a forlorn hope of propping up support for his party.

SNP leader Nicola Sturgeon, riding a tide of popularity, pledged that her party would work for the good of all Britons, not just Scots, in the new parliament.

Speaking to a crowd in Edinburgh, Sturgeon said that Scots and English voters who favoured progressive politics and an end to austerity should unite against the Conservative Party.

"If we work together we can lock out the Tories. We will work with others across the United Kingdom, that is my pledge," she said.

The SNP is set to take all but a handful of the 59 Scottish seats in the 650-member British parliament, a scenario that has caused panic in the two main parties.

With the Conservatives and Labour running neck-and-neck in polls, the SNP could be the king-maker in a hung parliament.

However, Labour leader Ed Miliband has ruled out a coalition with the SNP while Cameron has said the SNP having a powerful position in Westminster would be a nightmare which could lead to the break up of the United Kingdom.

Labour, which has long counted on a bedrock of support in Scotland, faces almost total wipe-out there at the hands of the SNP, whose popularity has soared in a remarkable turn of events since Scots voted to stay in the United Kingdom in a referendum on independence last September.

Many Scots feel that promises to give them more autonomy, made in the heat of the referendum campaign, have been broken.

A number of English politicians, backed by the London press, baulk at the idea of Scottish MPs voting in the British parliament on matters that do not affect Scotland.

A former Labour candidate for Perth, Doug Maughan, said on Wednesday he had decided to vote for the SNP after 20 years as a Labour member even though he did not support independence.

Maughan said Miliband's position that he would not come to any arrangement with the SNP made it clear he would rather see the Conservatives stay in power.

"That betrays an extraordinary contempt for democracy and a worrying attitude towards Scotland," he said in a statement. "I believe Labour has become too close to the Tories in its values and outlook."

That view has been echoed by many former Labour supporters - the party even looks likely to lose the Paisley and Renfrewshire South seat held by shadow foreign secretary Douglas Alexander to 20-year-old Glasgow University student Mhairi Black.

Paul Cairney, a professor of politics at Stirling University, said that if Labour failed to cut a deal with the SNP, it could get the blame for allowing the Conservatives back into power.

"My gut is that, in Scotland, if Labour refuses to be in government on the back of SNP support, it will bolster support for the SNP."

"The SNP can't make Labour do what it doesn't want to do, and they actually agree with Labour on the vast majority of the issues that will arise in the next Parliament," he told Reuters.

SCUNNERED

Sturgeon, who is also Scotland's First Minister and is not standing for election on Thursday, has said that a new referendum on independence is not the SNP's immediate aim.

She posed for selfies with children and old people in the rain outside the Scottish National Gallery on Wednesday.

One supporter, retired librarian Lindsay Levy, said she had left the Labour Party 10 years ago as it moved to the centre under Tony Blair and SNP social policies appealed more to her.

"It was New Labour that scunnered me," she said.

Asked about the vitriol coming from England, she said: "People I know in England say they would like to vote SNP if they could. They haven't got anyone whose policies they agree on."

Labour's rejection of a deal with the Tories was "just nonsense and part of the demonisation process."

An Edinburgh University student who had stopped to watch said however he feared for the future of United Kingdom.

"I'm a bit worried," he said, giving his name as Charlie.

He was from Buckingham, England, but was voting in Edinburgh against the SNP. He also thought it unfair that Scottish MPs would have a say in English matters.

(Writing by Angus MacSwan; Editing by Giles Elgood)