Can Ed Miliband lose this General Election?

Well, no one has ever lost money betting on the incompetence of party leaders. The Liberal Democrat leader, Nick Clegg, demonstrated yesterday that he doesn't even know who the leader of the SNP is. And, yes, the Tories are in the lead in some opinion polls.

But I believe Mr Miliband is going to have to dig deep into the well of incompetence to avoid getting the keys to Number Ten. He already has a three or four-point advantage because of out-dated parliamentary boundaries that favour Labour.

And even if the Tories are returned as the largest party by a handful of seats, they would be doomed. If David Cameron tried to form another coalition with the LibDems, it would very likely fall to the combined forces of Labour and the SNP.

It's simple arithmetic. The SNP are on course to be the third largest party in Westminster with nearly twice as many seats as the LibDems. They can't help being the deciding factor.

Mr Clegg can add and it's clear that, unlike Mr Cameron, Mr Miliband is going to have a cushion of pliant SNP MPs to help stop him falling out of government with a bump.

Now, of course, Mr Clegg has said he isn't interested in any "multi-party deals", but he doesn't need one because Nicola Sturgeon has nowhere else to go.

Anyway, as with the stock market, these things are "priced in" before the event so I suspect the LibDems are already thinking very carefully about whether or not to continue their alliance with the Tories. They certainly should be.

The Coalition has been an unmitigated disaster for the LibDems. It could reduce their Scottish party to one solitary seat in Scotland, Alistair Carmichael's in Orkney and Shetland, from the 11 they won in 2010.

Yes, the LibDems really did win nearly twice as many seats as the SNP at the last General Election. Now the SNP are on course to win twice as many seats as the LibDems in the entire UK.

It is said that, precisely because of the likely loss of those northern seats, the shattered remnants of the LibDems after May 7 will be more southern-oriented, Cleggish and more Tory; perhaps.

But even they would surely get the message that the only way for the LibDems to seek redemption is to distance themselves finally from the agents of their political downfall. The Tories anyway stand little chance of forming a stable government.

Another Tory alliance and the LibDems won't even need a taxi to ferry their MPs to Westminster. A tandem would probably do.

So, Mr Clegg or his successor will surely want to make a clean break with the Tory past. Most LibDem party activists have never been keen about being in Mr Cameron's pocket.

Above all, they have to atone for the broken pledge on tuition fees that hangs over every LibDem initiative like a bad smell.

Look at the LibDem manifesto launch yesterday, which featured a power cut half way through, plunging Mr Clegg into darkness. A portent, surely, of what could happen to his career after next month.

Their 2015 manifesto is as pledge-free as they could make it, but it still features headline commitments to spending on education and the NHS, as well as a lot of green policies like a legally binding decarbonisation target.

Inside, there are nods in the direction of old LibDem themes like land value taxation, living wage, scaling back Trident, more Europe, Lords reform and opposition to the Tories' £12 billion welfare cuts.

This looks much more likely to be delivered by a Labour-led coalition than a Tory one, especially since the Tories are moving sharply to the right across the board, but especially on the EU and welfare reform.

There is little in the LibDem manifesto that Labour would oppose; nor is there much that the SNP could object to in a Queen's Speech based on similar policies. There would be cross-party agreement on federalism, Lords reform, the Smith reforms, climate change, welfare, Europe.

The parties have different timetables for eliminating the fiscal deficit but no one believes anything any party is saying on fiscal affairs. Certainly, there are no obvious fiscal red lines between Labour and the LibDems.

Neither Mr Clegg's successor nor Mr Miliband need to do any kind of explicit deal with Ms Sturgeon because she cannot be seen to be helping the Tories into government.

Mr Cameron might cry foul and say that the LibLabs are in Ms Sturgeon's pocket, but I really don't believe this claim would stand up. They could say truthfully that they haven't even spoken to Ms Sturgeon about any agreement.

The LibLabs just need to put their Queen's Speech before Commons and let the parliamentary numbers do the rest. They can't be expected to force the SNP to vote against them, after all. In coalition, the LibDems provide Labour with cover against the charge that they're doing a deal with the SNP.

The Daily Mail will claim that Nicola Sturgeon is trying to rule England. But this would make no more sense than claiming that the Northern Ireland DUP want to rule England by always voting with the Tories and Ukip. It's parliamentary democracy working fairly and squarely.

And the alternative for the LibDems would be to go back into coalition with the toxic Tories and get themselves implicated in deep welfare cuts, an in-out referendum on Europe, tougher immigration policies and a lot of other nasty stuff.

There is another question that is being talked about quietly in Westminster circles: stability. Politicians and commentators in the bubble are worried that a succession of failed coalitions, with a rabble of little parties chopping and changing, would be bad for democracy.

This is why at the end last year there was speculation about the possibility of a Labour-Tory grand coalition to provide a degree of basic government stability, perhaps after a second inconclusive general election.

This has been looked at and dismissed by anyone with any common sense because it would be a disaster for both the main parties, but particularly for Labour. Moreover, it could simply fuel the anti-establishment forces.

Nothing could better confirm the claims of the SNP that the Westminster parties are "all the same" than for Labour and the Tories to become one government.

A Liberal-Labour administration with support from the SNP might not look all that stable, but it would at least have a chance of running the full term. The SNP, contrary to belief, don't actually want chaos in Westminster.

Ms Sturgeon wants the kudos of pulling Labour to the left, winning concessions on home rule and perhaps reopening the question of Trident. The SNP know all about minority government and sense that this could work.

If there is the slightest twinkle in Ms Miliband's eye, then it might be because the happy warrior is beginning to sense this also. A LibLab coalition just seems the most sensible solution for government in the new multi-party age.

Mind you, that probably means it won't happen.