Trying to find Conservative voters in Sedgefield, the sprawling Durham constituency that was Tony Blair’s political home for 22 years, might seem enough to get a man down. But this is not the most fruitless mission ever undertaken by Scott Wood, a former tank commander.

That mission would have been 12 years ago when, on Mr Blair’s instructions, he led his regiment around Iraq in the hunt for weapons of mass destruction.

“My direct instructions were to find the smoking gun, but nothing was found,” he says, parking his car in Newton Aycliffe for another afternoon of canvassing.

“My regiment was spread from Basra to Baghdad. We were forward of the Americans and all wearing NBC [nuclear, biological, chemical] suits. I remember the brigade commander turned up on the way into Basra. He told us, ‘Well you can get those [suits] off for a start.’

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“I didn’t need to be told twice. You sweat buckets in those. We ended up doing humanitarian work, but before that we’d be sent to all sorts of [places], munitions factories mainly. If a soldier thought something might be chemical, we’d be sent in with our swabs, but we never found a thing. We had anthrax monitors. They never returned a single reading.”

Scott Wood, a former tank commander, is from a mining family in County Durham

You might imagine that, in this truly unwinnable but famous seat, the presence of an Iraq war veteran who experienced firsthand the pointless search for WMDs used by Blair as a reason to invade is a clever stunt by Conservative Central Office. But it’s not.

Mr Wood is a local guy from a mining family that hasn’t been averse to sending the odd vote Mr Blair’s way over the past 30 years.

Now 40 years old, he runs an American diner in Darlington, the neighbouring constituency. It’s his home town. He stood there first but lost the selection by a single vote.

“Tony Blair knocked on my door once, years ago,” he says. “I spoke to him for 10 minutes. He said, ‘Can I count on your vote?’ I said, ‘No.’ Him and his entourage turned around and walked off.” Picking up the stack of leaflets out of the boot, he does a quick risk assessment. The car has large Conservative Party logos on each side. “No, no, it’ll be fine here. If I was up in Trimdon I would have to take those off. It would be attacked. It would. It really would.”

Tony Blair meets troops during a visit to Basra in 2004 (Getty) (Getty Images)

Trimdon, an old pit village in the north of the constituency, has been all but a no-go area for whatever masochistic Tory has pitched up here over the years. “An elderly lady used language on me that I couldn’t believe. It was worse than anything I’d ever heard in the army,” he says.

Usually, fighting an unwinnable seat is a rite of passage, but Mr Wood is here because it’s his home. He is also, perhaps a little ridiculously, not completely giving up on pursuing a surprise victory. “If enough Labour go to Ukip, and I put on a few thousand, it’s not impossible. That would be a story, wouldn’t it?”

In pictures: Experts' predictions for the General Election - 26/04/15 Show all 10 1 /10 In pictures: Experts' predictions for the General Election - 26/04/15 In pictures: Experts' predictions for the General Election - 26/04/15 Andrew Hawkins (ComRes) “This is an election of wild promises and political cross-dressing; so no differentiation, no breakthrough, no majority. The most likely outcome is Ed Miliband in No 10 because only he will be in a position to work with enough parties (that is, the SNP) to form a workable government.” Andrew Hawkins In pictures: Experts' predictions for the General Election - 26/04/15 Joe Twyman (YouGov) “As each day passes and the Conservatives fail to increase their vote share, the likelihood of Ed Miliband becoming PM (albeit still with a minority) grows. That’s due to the continued performance of the SNP in Scotland and former Lib Dem voters propping up Labour in England.” In pictures: Experts' predictions for the General Election - 26/04/15 Ben Page (Ipsos MORI) “A better week for Ed Miliband than for David Cameron – personal ratings improving, and the betting markets moved in his favour. The poll numbers have him ahead by a whisker which, combined with the electoral maths, makes him more likely to be able to form some kind of government on the raw numbers right now. However, Cameron will be hoping for a 1992 moment when ultimately voters can’t quite bring themselves to try someone else – and 38 per cent of voters still say they may change their mind.” In pictures: Experts' predictions for the General Election - 26/04/15 Rick Nye (Populus) “The Populus/Hanover Predictor has Ed Miliband ending up as Prime Minister in more than five out of six simulations we run.” In pictures: Experts' predictions for the General Election - 26/04/15 Nick Moon (GfK) “Tories most seats, SNP 45 or more, Ukip fewer than five: minority Labour government.” In pictures: Experts' predictions for the General Election - 26/04/15 Damian Lyons Lowe (Survation) “Ukip’s vote share is prone to be squeezed, benefiting the Conservatives, while the SNP’s onslaught on Labour continues. Based on three UK/Scotland polls, I am upgrading the Conservatives and the SNP, and downgrading Labour. Both the Lib Dems on 30 seats and Ukip on 5 to 10 remain unchanged.” In pictures: Experts' predictions for the General Election - 26/04/15 Michelle Harrison (TNS) “Still no change, but Nicola Sturgeon goes from strength to strength in Scotland. For me, who the biggest party is will hinge on the crucial marginals. But what ultimately wins – safety first, for the Tories, or Labour’s ‘get out the vote’ ground war?” In pictures: Experts' predictions for the General Election - 26/04/15 James Endersby (Opinium Research) “Our poll today shows a one-point Tory lead, statistically a tie. It’s going to be incredibly tight. Labour and the Tories would do well to be negotiating with the smaller parties behind the scenes. In the likely event of a hung parliament, we’ve been testing various combinations of coalition. Labour teaming up with the Lib Dems would be more popular than with the SNP, which in turn would be more popular than a Tory/UKIP scenario.” In pictures: Experts' predictions for the General Election - 26/04/15 Martin Boon (ICM) “Not much going on really, and no reason to change my mind. Tories by a couple of points. In pictures: Experts' predictions for the General Election - 26/04/15 Lord Ashcroft (Lord Ashcroft Polls) He refuses to make predictions. “My polls are snapshots, not predictions.” Rex

If the impossible is to be achieved, not many are going to be coming from Newton Aycliffe. The early responses to his leaflets, delivered with Tiggerish enthusiasm, range from “No, I’ve never voted” to “No, I don’t give a shit”.

But he has a line for everyone. “Don’t you care about jobs? Bringing more jobs to the area?” “I’ve got a job. Why do I need another job?”

“Don’t you care about pensions? Your pension’s gone up.” “My state pension’s gone up, but my company pension’s gone down. It doesn’t make any difference. I’ve never voted and I never will.”

More generally, he is a symptom of a confused electorate, of the blurred battle lines. Mr Wood, beyond a doubt, thinks he is on the side of those working hard on low incomes. The Labour Party, of course, thinks the same – so how do you know what to believe? “Well, they voted against raising income tax thresholds for the poorest people. That shows you’re not the party of the working class any more.”

It’s a compelling point. One chap, in tracksuit bottoms and a baseball cap, is almost convinced, though he is two-thirds of the way through a can of super-strength cider. It’s only 1pm and it doesn’t look like his first.