Ed Miliband yesterday left the door open to a Labour-SNP coalition after the General Election – as the latest polls point to a ‘Braveheart battalion’ of nationalists storming Westminster.

In a speech to party members in Edinburgh, led by Jim Murphy, the Labour leader ignored calls from his own frontbench, led by Shadow Chancellor Ed Balls and Health Spokesman Andy Burnham, to rule out a deal with Nicola Sturgeon’s party.

Last week a poll by Tory peer Lord Ashcroft put the SNP on track to increase its representation at Westminster to 56 of Scotland’s 59 seats, up from just six seats now.

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In a speech led by Jim Murphy (left), Ed Miliband (right) ignored calls from his own frontbench to rule out a deal with Nicola Sturgeon's party

This means that dozens of nationalist candidates are knocking on the door of the Commons.

They include Tommy Sheppard in Edinburgh East who, as The Mail on Sunday has previously reported, left aggressive messages about the Monarchy during the Royal Wedding – including the line ‘off with their heads’ – and Mhairi Black, aged just 20, who has talked about headbutting her Labour opponents in Paisley.

The SNP’s projected success could cancel out Labour gains in other parts of the UK, leading to a dead-heat between the two main parties – and allowing nationalists to play ‘kingmakers’.

Many Labour MPs think the only way to avert a humiliating collapse is for Mr Miliband to tell voters he won’t deal with the nationalists, to persuade anti- Conservative voters that a vote for him is the only way to remove David Cameron from Downing Street.

However Mr Miliband barely mentioned the SNP at the Scottish Labour spring conference. The Labour leader said: ‘The Tories could wreak havoc in Scotland without winning a majority by being in government as the largest party.’

...AND JUST LOOK WHO WILL BE MARCHING ON THE COMMONS! Tommy Sheppard - Edinburgh East Sheppard is an unreconstructed republican who tweeted ‘off with their heads’ during the Royal Wedding in April 2011 and said ‘this might be a good time to declare a provisional government’. Unreconstructed republican: Tommy Sheppard Mhairi Black - Paisley and Renfrewshire South The student, who is tipped to beat the Shadow Foreign Secretary Douglas Alexander at the age of just 20 – which would make her the Britain's youngest MP – wants to headbutt ‘fat-cat Labour councillors’ and tweets about her boozy antics. Future MP? 20-year-old student Mhairi Black Paul Monaghan - Caithness, Sutherland and Easter Ross Monaghan was suspended in 2008 from his job as head of planning and development at Northern Constabulary, a Scottish police force, after circulating an unflattering email about his boss. Paul Monaghan: Caithness, Sutherland and Easter Ross Martin Docherty - Dunbartonshire West Docherty issued a call to arms to nationalist supporters in January, with the volunteer activist urging voters to take the opportunity to ‘hold Westminster’s feet to the fire’. Martin Docherty: Dunbartonshire West Tasmina Ahmed-Sheikh - Ochil and South The ex-soap actress was a Tory and then briefly a Labour party member before she signed up to the SNP. As a Tory she described Alex Salmond as ‘hopelessly out of his depth’. Ex-soap actress: Tasmina Ahmed-Sheikh Alison Thewliss - Glasgow Central Thewliss boasted that she used Labour campaign literature to wipe her bottom. The councillor, who could topple former Scottish Labour deputy leader Anas Sarwar, also wrote in 2007 about her Labour rivals: ‘Can I hope some of them keel over?’ Glasgow Central: Alison Thewliss Phil Boswell - Coatbridge, Chryston and Bellshill Boswell posted messages on social media last month praising anarchy in Greece. The oil engineer said: ‘It’s about time we did like the Greeks and disempowered the corrupt self-serving establishment parties.’ Phil Boswell: Coatbridge, Chryston and Bellshill George Kerevan - East Lothian The former member of the International Marxist Group told November’s SNP conference that the UK has a ‘disastrous economy whose banking system is an organised criminal conspiracy’. George Kerevan: East Lothian Advertisement

But he failed to spell out whether his own party would be willing to strike a deal with another party if it does not win a majority.

Mr Cameron responded by raising the spectre of a left-wing axis between Labour and the SNP. He said: ‘If you thought the worst outcome for this Election was a Labour government led by Ed Miliband, think again.

'You could end up with a Labour government led by Ed Miliband – propped up by the Scottish National Party – an alliance between the people who want to bankrupt Britain and the people who want to break up Britain.

'And even today, Ed Miliband will not rule out a deal or backing from the SNP. If he cares about this country he should do so.’