Today's YouGov poll for The Sun, showing a Conservative lead of just four percentage points, raises one of the most intriguing and specialised sub-questions of the great hung parliament dilemma.

Assuming a roughly uniform swing, and if YouGov's methodology is sound, that poll suggests that the Tories would win more votes and the Labour Party would win more seats.

That is Nick Clegg's nightmare. It was for several excruciating minutes the nightmare of Danny Alexander, MP for Inverness and Clegg's chief of staff, on Radio 5 Live on Monday. As Iain Dale spotted, he was skewered by Stephen Nolan on whether the "mandate" that the Liberal Democrats would respect would be measured in votes or seats. 

Alexander appeared not to know, which is surprising, because he must have discussed it with his boss. Worse, he did not appear to know that his boss had answered that very question in an interview with The Independent the week before. I apologise to Clegg and to Andrew Grice for not having noticed it myself, but you might have thought that Alexander would know of it. Clegg said:
 

In other words, he wants to keep his options open as much as possible. Sensible, really, but I wonder if it is a position that will survive a general election campaign. 

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