"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”.

“It’s an absolute farce,” said John, 70. “Why did he have to resign his bloody seat? Think of the cost.” John will be voting for Davis, though, because he likes him and because he’s a Conservative – but he thinks he’s a stupid bugger, too.

The other phrase you hear a lot is “42 years!” – as in “42 days? You should bang them up for 42 years!” The people of Haltemprice & Howden may have many political causes for which they feel sympathy, but the civil rights of Muslim potential terrorists is not one of them. This is a very white constituency and a very right-wing one. It is a strange neck of the woods; flat, low-slung land nestled between the arable faux-uplands of the Yorkshire wolds and the grim chemical industries of the Humber, with Hull and Doncaster baleful presences in the middle distance. It is also, unexpectedly, Britain’s 10th most prosperous constituency, but there’s not much sign of money about.

“It’s all stuffed under their mattresses,” chuckles the man himself, David Davis, over barbecued ribs and roast duck in Howden’s Golden Cottage Chinese restaurant. Well, indeed – and these two stereotypical Yorkshire qualities of thrift and a reluctance to make a fuss may dispose the hitherto loyal electorate against Davis, whose venture is widely seen as unnecessarily costly and the result of hubris. Few, mind, will vote against him; most just won’t turn up. Davis reckoned the turnout could be below 20%, although he may have been underestimating for later effect.

However, we might all be surprised if it exceeds 30%, which suggests this principled stand – and I believe it is one of principle, even if enhanced by a boredom with the stultifying politics of David Cameron’s Conservative party – has not captured the imagination of even those most kindly disposed towards the man. Which is sad and does not bode well for his future. He expects at least a term on the back benches, assuming the Tories win next time around. He professes not to be bothered and, catching his tone, I think I believe him about this, too.

He’s not bothered either by the apparent disaffection of his constituents; he is playing a longer game, he says, dragging the issue to centre stage. Change in public attitudes may take a lot longer to effect – just as it did with ID cards, he says.

You cannot doubt his abhorrence at the rapid march of the invasive state and the erosion of our civil liberties. A right-wingish Tory may be an unlikely standard bearer in the battle against creeping authoritarianism, but he’s what we’ve got.

Meanwhile, in the far east of the constituency where the green fields suddenly and unwillingly become that thing called Hull, David Icke, the former sports presenter who once claimed he was the son of God, is unveiling his manifesto. Icke believes the world is ruled by alien lizards and he is worried we are turning into an alien lizard-based fascist state. Yep, he’s standing too.

Why are all the journalists here today? The answer is in a phalanx of cars outside a school near Brough, with PR people and coppers getting above themselves: “Come on everyone, get back, get back.” Is it royalty? Nope, it’s Cameron. In at 17.09 on the clock, two questions allowed from the press, a chat with Davis and some school-kids, then out of the place like a rat up a drainpipe at 17.37.

I counted him in and I counted him out. He disappeared to some public meeting in Selby. Stepping out of the car, he greeted Davis as if he desired him carnally. I asked him if he would be back next week to do another stint in support of his brave and principled candidate. Cameron turned to me and said: “Are you out of your mind, you moron? No, no, a thousand times no.” Actually, he didn’t say any of that, apart from “no”. He chuntered on about the shadow cabinet being up all week, so he wasn’t really needed, etc.

Then he went to talk to the kids and, watching him do so from behind a pillar, I was suddenly struck by the notion that maybe Icke wasn’t so very wrong after all. Maybe it is all about evil alien lizard creatures.

According to the experts, to the Westminster journalists and pundits stamping around outside this school, wondering if they’re in time for the last train home, Cameron has played the whole thing “brilliantly”. Really? Beyond the neat redbrick cottages and manicured bowling lawns of Howden, there’s evidence that the public think Davis is doing something admirable, even if they do not agree that potential Muslim terrorists should be afforded the same legal rights as the rest of us and instead should be hung up by their tongues and whipped.

It is the same sort of impulse that suddenly makes Tony Benn a respected and popular figure. That people would like our politicians to be energised by opinion, even if it is the sort of opinion they do not share. They might have had a higher opinion of the Labour party if it had opposed Davis rather than ducking out. Forget the morality of the issue for a moment – even in political terms, Labour had little to lose; its vote share in Howden is minuscule.

Make the issue solely about 42 days, adopt a strong candidate and I reckon there would be at least a 5% chance that Labour would win (Davis, incidentally, puts it a lot higher).

Losing would be no disgrace; the party would almost certainly see an increased share of the vote, given the absence of Liberal Democrats. But there is no nerve or chutzpah left in Labour, which is one reason why it is hurtling towards general election oblivion. Nerve and chutzpah and the intimation of personal sacrifice are the reasons why Davis is liked by voters – and liked even more by the Conservative associations. He will be an interesting figure after the next election, camped out on the back benches with the soul of his party in his hands, although he insists he will be loyal. Let’s see.

I must admit I rather like the situationist aspect of this by-election, the notion that the usual apple cart has been upended. When Davis announced his resignation, two things happened simultaneously: everybody in the Westminster village avowed he had gone mad, or at least terribly miscalculated. And outside Westminster the messages of support flooded in for the man. He has without question wrong-footed the Westminster machine and if he has also wrong-footed himself in the process, then so be it.

Anyway, I repaired to the White Horse, the better to get to know another candidate in this hugely entertaining election.

As a journalist it is important to do one’s research, to devote time and energy to what sometimes appear arcane causes. Which is why I spent time and energy examining the electoral qualifications of Gemma Garrett, who is also – by coincidence – Miss Great Britain.

I liked her. Her only two policies are: give the army better equipment and protection and help single mothers. She is also pro-42 days. She’ll come a good third, I reckon. Go, Gemma, go. Howden could do worse.

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