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Alex Salmond, Scottish first minister, has declared that “independence is closer than it has ever been”, as the Better Together No campaign admitted that the polls are narrowing and nerves began to fray.
Mr Salmond said he was still the underdog in the campaign but that Scotland was in the grip of a “democratic sensation” with large-scale voter registration ahead of the September 18 independence referendum.
Better Together strategists admit that Mr Salmond pulled off a masterstroke last month by suddenly switching his tactics, warning that only independence would save the NHS from cuts by a Tory government at Westminster.
Mr Salmond’s pitch to voters that they should vote for independence to save the NHS has seen undecided Labour and Liberal Democrat supporters switch to the Yes campaign in substantial numbers in recent days.
In Conservative circles there are recriminations about the failure of Alistair Darling, leader of the Better Together campaign, to rebut Mr Salmond’s argument in the second and final televised leaders’ debate last month.
Douglas Alexander, shadow foreign secretary, who is overseeing the Labour campaign in Scotland, and Alistair Carmichael, Lib Dem Scottish secretary, will also face criticism if the polls fail to improve.
Ed Miliband, Labour leader, will travel to Scotland on Thursday with a simple message to his supporters that he will win the British election in 2015 and “save you from the Conservatives”.
Mr Miliband hopes to convince voters that Mr Cameron’s party is falling apart and that the defection of Douglas Carswell, the Tory MP for Clacton, to Ukip last week was evidence that a Labour general election victory next May is coming.
Privately some Conservatives joke that Mr Carswell’s defection might be bad news for Mr Cameron but might help to persuade left-leaning Scotland that the prime minister is on his way out.
Mr Cameron is not visiting Scotland this week in spite of narrowing polls: a YouGov survey for The Sun put the No camp on 53 and the Yes camp on 47, once undecided voters were excluded.
His advisers have told him that his presence may be counter-productive, especially among the “don’t know” working class voters of the west of Scotland who are now the focus of active campaigning by both sides.
Mr Cameron presided over Cabinet talks on Scotland where ministers agreed there should be no change of tactics in the final days of the campaign.
The Better Together campaign insists its positive message on the benefits of the union and its warnings about the economic risks remains the right one.
But the campaign is hoping to mobilise Labour heavyweights to deliver the message in the final days of the campaign, with names such as Gordon Brown, John Prescott and Ken Livingstone being mentioned.
Meanwhile, the chairman of the Scottish Police Federation warned campaigners and politicians against using “intemperate, inflammatory and exaggerated language”, after a senior No campaign source suggested that polling day could descend into “absolute carnage”.
Jim Murphy, a Labour MP campaigning in Scotland, suspended his countrywide soapbox tour for 72 hours after accusing local Yes campaign groups of orchestrating confrontations at his street meetings. The MP was pelted with eggs in Kirkcaldy last Wednesday.
Separately, Danny Alexander, Liberal Democrat Treasury chief secretary, published a letter from a senior Brussels official saying that an independent Scotland would not be allowed to join the European Union if it unilaterally adopted sterling without the consent of the rest of the UK.
Olli Rehn, former EU monetary affairs commissioner, said a “sterlingisation” arrangement would debar Scotland from joining the EU because it would not have its own central bank.
The option is one of several “Plan Bs” Mr Salmond has said he would consider if the rest of the UK rejected a currency union, although he insists that such a pact would be agreed.
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