Latest poll (Sunday Times/YouGov): Labour nine seats short of a majority.

"Gordon Brown on course to win election" is a headline almost no one would have expected to see at this stage of the electoral cycle. But today's YouGov poll confirms what a terrible start the Conservatives have made to their campaign. It puts the Tories on 37 per cent, just 2 points ahead of Labour, and the party's lowest lead since December 2008.

If the figures were repeated on a uniform swing at the election, Labour would emerge as the largest single party in a hung parliament, nine seats short of an overall majority.

The poll is particularly alarming for the Tories for two reasons. First, it suggests that the potential number of Labour voters is far higher than previously thought.

Second, it suggests that the Tories suffer when their policies come under sustained scrutiny. Brown's call for voters to "take a second look at us, and a long, hard look at them" seems to have resonated with the media and the public.How else can we explain the Conservatives' precipitous decline?

New Statesman poll of polls

Labour 28 seats short of a majority.

As I've pointed out before, the fragile nature of the economic recovery appears to be working in Brown's favour -- it strengthens his argument that immediate spending cuts would damage the economy and upsets the Tories' message. The poll also confirms that the bullying allegations against the PM have done no damage to Labour's support. It may be that the voters actually rather like being led by someone with a bit of a temper.

Brown will surely now be tempted to call an election while the political momentum is with Labour and go to the country in April. But I'd still be surprised if he doesn't plump for 6 May in order to avoid the cost of holding two separate elections.

As a word of caution to Labour optimists, it's worth pointing out that there's still almost no chance of Brown winning an overall majority. Boundary changes mean that Labour's 66-seat majority has fallen to a notional lead of 48. This leaves Cameron with only 24 seats to win to knock off Labour's overall advantage. I expect the Tories still to be leading in the key marginals.

But for Labour to emerge as the largest single party would be an astonishing turnaround. That the Tories are still struggling to defeat a government battered by recession and the expenses scandal is quite remarkable.

Can Cameron lead a successful Tory comeback? He has done so before, of course, in the run-up to the election-that-never was. We'll begin to find out later today.

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