Yes leads in Scots poll shock

Senior aides are worried that she will be pitched into a constitutional crisis that threatens her status as Scottish head of state and her oath to uphold the Church of Scotland. “If there is a ‘yes’ vote, that puts us into uncharted territory constitutionally,” one aide said. “Nothing is certain. Her being Queen of Scotland is not a given.”

The new poll last night sent shockwaves through Westminster as Tory MPs warned that David Cameron would have to resign as prime minister if Scotland voted to go it alone. Several Conservative MPs are prepared to go public and demand he quit, and two Tory ministers have warned colleagues that they would also feel compelled to resign if there were a “yes” vote. Conservative whips revealed they were “aware” that a small number of MPs might seek to use such a crisis to oust Cameron.

Recriminations also engulfed Labour, with insiders calling for Ed Miliband to sack the party’s election co-ordinator, Douglas Alexander, who is blamed by many for the reversal of fortune.

In a grave embarrassment for Miliband and Alistair Darling, the poll reveals that Scottish Labour voters are fast deserting the Labour-led unionist campaign: 35% will now back independence — nearly double the 18% a month ago. The under-40s and working-class and female voters are also shifting towards the “yes” camp.

In a second blow to Labour, just one in three voters trusts arguments made by Darling, the head of the Better Together campaign, or Gordon Brown, its highest-profile campaigner. Both Cameron and Miliband score a dismal 23%. In contrast, Salmond and his deputy, Nicola Sturgeon, are trusted by more than 40% of Scottish voters.

Miliband raised the possibility last night of border controls with armed guards between Scotland and England. “If you don’t want borders, vote to stay in the United Kingdom,” he said. Under EU rules an independent Scotland joining the EU would have to be part of the area of “free movement” and would not be allowed to have its own border controls. At present UK border entry points are guarded by armed police. The same might apply to the England-Scotland border after a “yes” vote.

Today’s poll is particularly significant since YouGov has traditionally found less support for independence than some other pollsters.

All three main parties seeking to defend the union will launch a PR blitz this week to stem their haemorrhaging support. The prime minister will travel to Scotland today to visit the Queen at Balmoral, for what will now resemble crisis talks. They will make a joint public appearance at a church service.

Cameron is planning a final speech a week tomorrow, telling Scots that they have the “best of both worlds” by remaining part of the UK.

Miliband has ordered 100 of his MPs to campaign in Scotland and plans a joint appearance with Gordon Brown this Friday. John Prescott and John Reid will also hit the campaign trail. In a speech yesterday Douglas Alexander promised that the unionist parties would deliver “a stronger Scottish parliament” to swing floating voters.

The prime minister has repeatedly ruled out resigning, insisting “emphatically” on Thursday that he would not quit. A separate YouGov poll of voters across the whole of the UK today finds that 22% of voters think he should stand down.

But MPs from all wings of the Conservative party have told The Sunday Times they think Cameron will be duty-bound to stand down if he becomes the leader who lost the union.

Several compared him to Lord North, the first prime minister to be forced out of office after losing a vote of confidence in the House of Commons in 1782, after he presided over the loss of the American colonies.

MPs say the view that Cameron may be forced to stand down is shared by some cabinet ministers. One senior backbencher said: “This is a mainstream view in the parliamentary party. It goes well beyond the usual suspects. Two people who are ministers have said to me that they feel they would also have to resign.”

One MP said: “I can’t see how Cameron can stay, frankly. He thinks he can just cruise on when the union of 300 years has been dissolved. Someone’s got to go. Heads have got to roll. The idea that something like this happens and nobody loses their job over it is nuts.”

A former minister blamed the prime minister for letting Salmond dictate the timing of the referendum. “There have been mistakes about this campaign,” he said. “We should never have allowed Salmond to have determined the question. We should never have allowed him to determine the date.

“The consequences for the whole of the United Kingdom of a ‘yes’ vote to make Scotland a foreign country are absolutely cataclysmic. The nation will be pitched into turmoil. That will infect the capital markets, the stock market, everything.”

MPs are refusing to break cover now because they do not want to boost Salmond’s campaign, which rests, in part, on exploiting anti-Tory feeling among many Scottish voters. But one prominent MP said some would speak out if there were a “yes” vote.

Another senior backbencher said: “It’s a golden opportunity for a lot of people who hate Cameron and are just looking for an opportunity to get rid of him. There will be a push to topple him and get in a caretaker government. Today walking around the lobbies the grumpy discontents are very excited about the idea. The Boris campaign is quite excited about the idea. All the usual suspects will gather and circle.”

The plotters want the MP John Randall to stand down and force a by-election in his Uxbridge and South Ruislip seat so Boris Johnson can return to the Commons to take over as leader. Those plans are rejected by Johnson’s allies, who say that any move against Cameron would be “a disaster for Boris”.

In the event of a “yes” vote, Whitehall sources say the prime minister will hold an emergency Cobra meeting to help combat panic in the financial markets.

He will also face pressure from Tory MPs to pass legislation banning Scottish MPs from voting on English laws in the year between the 2015 election and the 2016 deadline for an independence deal. The YouGov poll of UK voters shows that 4 out of 10 think Scottish MPs should not even be allowed to stand next year if Scotland opts for independence.

As the recriminations flowed, senior Tories criticised Labour’s failure to shore up its own vote in Scotland. “The reason Labour are up there in force is that they’ve got to get their side of things fixed,” a No 10 source said. “Scottish Conservatives are rock-solid but Labour hasn’t delivered.”

Unionists on both sides of the border are venting frustration at the quality of the Better Together team, which they claim lacks vision and ability.

Better Together figures have christened Alexander “Rain Man” after the autistic character played by Dustin Hoffman because “people cannot connect with him”.

“It’s a campaign with no vision and no direction — the general feeling is that the people are just not up to the job on the Labour side,” one unionist insider said.

A Labour frontbencher said Miliband should fire Alexander as his general election co-ordinator. “Douglas is showing why he shouldn’t be put in charge of a whelk stall let alone a major campaign. Even if there’s a ‘no’ vote, we don’t want our fate in his hands next year.”

Alistair Carmichael, the Scottish secretary, has pledged to hold a conference on devolution within weeks of a “no” vote. But there is incredulity in Tory and Lib Dem circles that Labour has refused to go as far as them in offering the Scottish government complete control of income tax.

Rory Stewart, the chairman of the defence select committee, criticised the leaders of all three main parties for failing to make the positive case for the union.

He said: “A ‘yes’ vote would represent a failure of the entire political class. I think it’s the greatest constitutional issue we have faced for 300 years and it has not been treated like that. In the 19th century, this would have been like the Great Reform Act. It would have engaged the whole nation and its politicians for years.”

Stewart refused to call for Cameron to quit because “that would be a gift for Alex Salmond”. But he suggested the prime minister might be forced out: “Gladstone, for all his reputation, fell on home rule, which is a lesser thing than independence.”