If the Tories pick a good candidate and fight a strong campaign, they have a good chance of winning the Rochester and Strood by-election. This is my conclusion after visiting the town on Monday.

For Rochester is not Clacton, where the Tories are tomorrow likely to lose. It looks different, and more importantly it feels different.

The looks are what first strike the visitor. The Norman castle occupies a magnificent position overlooking the Medway. Behind it stands the yet more magnificent cathedral, much of it also Norman. And the houses around and beyond the cathedral are so attractive, and so full of interesting associations with half a dozen English monarchs and with the life and novels of Charles Dickens, that they compel an exploration on foot.

While Clacton was founded in 1871 as a seaside resort, and still feels quite remote, Rochester is on Watling Street, a main road for over 2,000 years. It can be reached much more quickly than Clacton from London. And once one has made a first tour of its architectural treasures, one feels irresistibly drawn (or I did) towards its second-hand bookshops.

In one of these delightful shops, I told myself I must stop browsing and start talking to people. So I asked Bob Peters, who has run City Books for the last seventeen and a half years, if he would care to say anything about the impending by-election, precipitated by the decision of Mark Reckless, the local Tory MP, to join UKIP.

“Well,” Mr Peters said, “Mark Reckless comes in here quite a lot. A very honest man. I think like a lot of people he’s concerned about immigration. Hundreds of thousands of people coming in who know what they’re entitled to. It does worry people, because we’re a small country. Perhaps we should all emigrate to Romania or Bulgaria.”

Why exactly does Mr Peters object so strongly to these immigrants? He went on: “A significant proportion of them come over not wishing to work. They are given assistance as to their rights. Let’s put it this way. We don’t want the mickey taken out of us.” He instanced an immigrant family with a large number of children who were therefore receiving a large amount in benefits. “That is taking the mickey.”

I mentioned that I had last visited Rochester during the general election of 2005, to write about Bob Marshall-Andrews, who had won the seat, then known as Medway, for Labour in 1997. Mr Marshall-Andrews tended to ignore the Tories and to concentrate on attacking his own leader, Tony Blair. At the Labour conference in 1997, Mr Blair had an approval rating in the polls of 93 per cent, but Mr Marshall-Andrews was not discouraged. “Seven per cent,” he said. “We can build on that!”

It turned out that Mr Peters remembered Mr Marshall-Andrews, who was another of his customers, with affection: “Very funny. I liked him.”

But nobody else mentioned Labour while I was in Rochester, and that party’s leadership has in recent days attracted adverse comment, by indicating that it does not intend to make a serious attempt to regain the seat.

Mr Peters explained why he intends to vote for UKIP: “It’ll be more than anything else to wake those who are in power up a bit.”

That is very much the feeling in Clacton, where I found, on an early visit for ConHome, enormous spontaneous support for Douglas Carswell, the first Tory MP to precipitate a by-election by joining UKIP.

In Rochester, few voters mentioned Mr Reckless by name, except for a number of people who thought he had behaved badly. He has contested this seat since the general election of 2001, very nearly won it in 2005 and actually managed to take it in 2010, but over this considerable period of time he has not built a personal connection with the voters to rival Mr Carswell’s.

At the Eagle Tavern, a friendly pub next to a stretch of Rochester’s medieval and Roman walls, there was a strong “plague on all your houses” feeling about the various political parties, including UKIP. In Clacton, I had found a strong desire to kick the established parties by supporting Mr Carswell. In Rochester, there was no sign of comparable support for Mr Reckless, and a greater tendency not to vote for anyone at all

One woman said of the forthcoming by-election: “I don’t think it makes any difference. They tell you everything, but UKIP will never make it into government. That means we’ve got to put up with more boring politics. I don’t think people are that bothered. Nobody’s talking about it.”

A second woman, in her early forties, said: “I’ve never voted in my life, I’ve never had hundred per cent trust in someone.”

First woman: “What they really need to do is live in the real world and live off the normal person’s wages.”

Second woman: “I noticed when I was working for the Post Office, the number of immigrants. Some of them were very aggressive. We’re an island and we’ve got too many people on the island and we’re going to sink one day. If I voted, I’d vote UKIP. But I just don’t trust what anyone says. The only reason I’d vote UKIP is I like what they’re saying about foreigners coming in. Within a week they’d get benefits. When I was working for the Royal Mail, you’d get ten men in one house. Lithuanians, Kosovans, they’re all living in one house, they’ve got wide-screen TV, flash cars. That’s what gets on my nerves. That’s what winds me up. I think they should be on a probation thing. I don’t think they should be able to get money straight away.”

But this second woman proceeded to draw distinctions between different groups of immigrants: “The Lithuanians and the Poles, they come into our country and they work. I’ve got friends who are Lithuanians and Poles and they’re hard-working people.” She then indicated some foreigners of whom she disapproves: “If you go down Chatham High Street [very close to Rochester], they own half of it. As soon as they’ve got an English girl pregnant they’ve got the right to stay in England.”

She described how the neighbourhood had changed since she was young: “When I was 13 years old I used to go bean picking and potato picking with my Mum. What happened was the Polish took over all the field work because they’d work for less money than what the English would. Now in the field work there isn’t one English person working in the fields, they’re all Polish. That’s what the English have lost. They’ve lost that field work.”

In the Crown Inn, at the other end of the High Street and next to the bridge over the Medway, a recently retired man said: “I was interested in voting UKIP to start off with. However I saw the defection of Mark Reckless at the time he did [just as the Tory conference was getting under way], he put me back, because I think that was disgraceful. So I’m still undecided but if anything it’s led me away…There are days when you announce you’re jumping ship and days when you don’t. I have heard it said he’s not a people person.”

This man expressed a general disillusion with politics: “What’s happened to the statesmen of this world? You want someone to take charge. And could you honestly trust any of them to take charge? I suppose I still lean slightly towards UKIP because of Europe – Europe has to be told where to get off.”

A woman in the Crown said of the by-election: “I think it’s going to be close. I really do. We’ve had a few defections at the weekend from the Conservatives, but nothing high-profile.”

A man said the Medway towns, including Rochester, Gillingham and Chatham, were noted for apathy: for a lack of enthusiasm for anything. There is a large working-class population here, which suffered heavy unemployment after the Royal Navy Dockyard at Chatham closed in 1984.

I am not sure whether “apathy” is the right word . But it is true that although people are very angry about immigration, the rebellious tone found in Essex is not so apparent in Kent. Many of the people I approached said in a firm but amicable manner that they simply did not wish to talk about politics. Others said they had never voted for anyone and did not intend to start doing so now.

One man in the Crown said of Mr Reckless: “I think he’s useless. The first important vote after he was elected, he failed to turn up for it, for a start.” This was a reference to a famous occasion in 2010 when Mr Reckless omitted to vote because he had drunk too much.

This Saturday, UKIP will open their new campaign centre in Rochester. It occupies what used to be The Angel Energy Centre, which offered “a vast array of crystals, gifts, handmade jewellery and natural organic bath products, combined with spiritual books, tarot cards and incense”.

The centre is in fact already open, but nothing much is yet going on there. In a sense, this is unsurprising: tomorrow UKIP is contesting two other by elections, in Clacton and in Heywood and Middleton. But it makes a marked contrast with the new UKIP headquarters in Clacton, which was immediately thronged with eager volunteers.

A Survation poll published three days ago in the Mail on Sunday suggested that UKIP is on 40 per cent of the vote in Rochester, with the Tories on 31 and Labour on 25. But Mr Reckless’s lead of nine points should be compared to one of 44 points for Mr Carswell at a similar stage in Clacton. Rochester is by no means a foregone conclusion, and a lot of people there are dubious about all the contenders, including UKIP.

One clear similarity between the two seats is that in both cases voters are very worried about immigration, and also about Europe. If the Tories are to maximise their vote in Rochester, they will need to give whatever reassurance they can on these subjects. Mr Miliband’s reluctance to campaign wholeheartedly may spring from his reluctance to campaign strongly on such themes, or else from his hope that UKIP and the Tories will inflict grave damage each other. But this was until 2010 a Labour seat, and for that party to surrender what used to be such promising territory without a proper fight does indeed look bizarre.