David Davis resigned his seat to fight a by-election in order to raise the profile of the issue of 42-day detention. Until then the opinion polls had shown the majority of people surveyed were in favour of longer periods of detention for terrorist suspects. I happen to disagree with that view, as does Davis, clearly, and he has taken his 'principled stand' in order to endure the good people of Haltemprice and Howden can hear the arguments, and presumably give a ringing endorsement to the former Shadow Home Secretary's view.

Of course, Davis did a deal with Cleggy beforehand to ensure he wouldn't have any significant opposition before he took his principled stand, and Labour decided to take no part in what it regarded as a stunt which would prove nothing. All of which is likely to affect turnout. The 12% of those who voted for Labour in the constituency in 2005 are unlikely to give a ringing endorsement to a right-wing Tory such as Davis, although from the tone of many libertarian left bloggers there may well be some who do want to be seen to be supporting not Davis, but his opposition to 42 day detention. So, he might pick up a small proportion of those 6,000 votes.

Given the Cleggy deal to effectively give the Lib Dem backing to Davis however, it seems reasonable to suppose that many of the 17,000 plus Lib Dem voters from 2005 could be expected to throw their votes behind David Davis.

That leaves the nearly 23,000 voters who supported Davis in 2005. How they vote, or at least, in what numbers they vote, will surely be Davis' measure of how successful his principled stand has been in winning the argument. Of course, in by-elections we have to accept that turnout is usually lower anyway, and with a foregone conclusion for the result turnout may be even lower than that . But a low turnout, in what Davis has effectively tried to turn into a referendum on 42 day detention, could deliver a nasty slap in the face for Davis, and his Leader David Cameron. If he is unable to get at least the 22-23,000 to match the Tory figures of 2005, he can hardly claim a ringing endorsement. So, what level of support for David Davis would be respectable enough for him to claim at least a moral victory for his stand?

Whatever the face-saving figure would be, from what Rod Liddle writes here in the Sunday Times, things ain't looking good:

"Stupid bugger." This is from an elderly bloke making his way up the main drag in Howden, East Yorkshire, past the Pet Empawrium, past the White Horse pub, up towards the butcher's, dodging past the camera crews and reporters. Off to his left there's a haggard geezer with long sideburns in a red jumpsuit, handing out leaflets, lurching in the manner of someone who has spent too long in the White Horse.

This is one of those loonies, one of the 26 fringeish candidates standing in the Haltemprice & Howden by-election: it is Lord Biro, who represents the Church of the Militant Elvis. He is not the target of my interviewee's scorn, however. Nor is it the neat, plausible and mild David Pinder, who is accosting people on the other side of the road in the cause of the New party (no relation to Oswald Mosley's old New party of the 1930s).

No, the "stupid bugger" comment, like all the "stupid bugger" comments hereabouts, was directed at the man who was until recently the respected local Conservative MP - David Davis. You hear the phrase directed towards Davis from pretty much whoever you talk to in Howden: in the Co-op, the pine-clad snug of the Wellington hotel, the olde-worlde sweetie shop. I couldn't find a single person who agreed with Davis's "act of principle".

I have no idea what the turnout will be. I do know that 5,000 students who are on the electoral roll are not around and that a lot of people will be on holiday. I suspect 50% ought to be considered a good turnout, but it could be a lot lower. Haven't got a clue to be honest.