One way or another, David Cameron will soon be a history man. In 12 days’ time, he will have pulled off his great gamble, prevailed in one of the most significant – and vicious – political contests in the life of this nation and won the referendum, or Britain’s membership of the European Union will be toast and he with it, leaving future historians to debate why a previously skilled and supple leader made such a catastrophic mistake.

David Cameron says state pensions could be at risk if Brexit becomes reality Read more

The campaign has not unfolded as Cameron anticipated when he fired the starting pistol. He didn’t foresee Boris Johnson and Michael Gove leading the Brexiters, he did not reckon with it being so poisonous between Tories and he didn’t think it would be so tough. By the final stretch, he expected to be sitting on a confident lead for In, not locked in a fight so tight that Remain campaigners talk of this being “squeaky bum time”.

Cameron comes as near as a politician ever does to conceding that the vote could be lost: “It’s clearly a very competitive referendum, it’s clearly very close.”

He also talks in a way that suggests he thinks his side needs to accentuate the positive arguments for membership: “We’ve got an incredibly strong case to say: look, if we stay in a reformed European Union, we’ve got a very bright future. A lot of businesses and investors will see Britain has decided its future in Europe and has got enormous opportunities around the world. I think we’ll see investment. We’ll see more jobs.

“All this is an exciting future and we need to get that across alongside the huge risks there are from leaving.”

Having said that, he is not going to stop playing that risk card which is his core argument for why it would be folly for Britain to take “a leap in the dark” by self-ejecting from the EU: “To people who say there’s been too much scaremongering, too much talk of dangers to the economy, that is what I believe.”

To his previous warnings about the perils of Brexit, he adds a new one when he cites the Institute for Fiscal Studies and other expert bodies in support of his contention that departing the EU would be so damaging to the economy that it would create “a black hole” in the public finances that would entail spending cuts “to the tune of something like £40bn”. That, he says, would mean the NHS and pensions could no longer be guaranteed ringfencing from cuts: “Those things are on the ballot paper and they are at risk.”

Facebook Twitter Pinterest On Michael Gove’s position: ‘Even if one can find experts frustrating … the idea that you brush all these warnings aside is absurd.’ Photograph: Andy Hall/The Observer

We remind him that Gove – still, though it may sometimes be hard to believe, a member of his cabinet – has dismissed the many warnings from expert bodies of the perils of Brexit on the grounds that “people in this country have had enough of experts”. Cameron responds with a withering contempt that suggests he’s had enough of his erstwhile friend: “I thought that was a telling phrase because, in fact, even if one can find experts frustrating, you wouldn’t buy a house without listening to one, you wouldn’t build a bridge. The idea that you just brush all these warnings aside is absurd.”

He was bitterly disappointed with Gove’s decision to join the Outers, but at least credits him with acting from principle because he “had a very longstanding view about getting out of Europe”. But there is only boiling rage towards Boris Johnson within No 10. It is not officially admitted, but universally assumed, that the prime minister must have licensed the full-frontal attack on Johnson by cabinet minister Amber Rudd, when she told a TV debate audience: “We need to look at the numbers. I fear the only number Boris is interested in is the one that says No 10.” A good line, wasn’t it?

Cameron laughs, takes a beat to consider how to answer, then effectively endorses her characterisation of Johnson as a man driven only by his unprincipled ambition: “It was a very good debate. I thought she was very strong. I think she’s a real, real star. She says it as she sees it and she does it very strongly.”

He launches his fiercest broadside yet on the Tory Brexiters. They have comprehensively lost the argument on the economy, he contends, and as a result have sunk to singing along with the anti-immigrant tunes of Nigel Farage.

“When you look at the Leave campaign, it is beginning to sound very much like Farage’s Britain. They’ve bought into the Farage argument that everything’s disastrous. When they say take the country back, I think sometimes they mean take the country backwards to when it was the sick man of Europe. In Farage’s case, immigrants are demonised as being rapists and all the rest of what comes with Farage’s Britain.”

Does that disgust him? “Yes, like a lot of the things he says. I’ve been watching this guy for a decade now. You go back and you add it up – ‘Chinese people are Chinks, gay people are fags, women should breastfeed in a dark corner of the room’, all the rest of it. He’s got a track record as long as your arm and there is a danger that the Leave campaign is morphing into the Nigel Farage Little England campaign. And I would say that’s not what this country is. It’s not what our country wants to be. It’s not the country I want for my children. So don’t vote for Nigel Farage’s vision of Britain on 23 June.”

It is evident, though, that the Outers are focusing so heavily on immigration because it strikes a resonant chord with a significant proportion of voters. Cameron doesn’t really argue when we suggest that he and Remain have struggled to answer the Outers on immigration.

“It’s difficult in the sort of soundbite culture in which we exist to try to make a complicated argument. But the complicated argument is that Britain benefits from immigration, has done in the past, will do in the future. You can see that in our public services, you can see that in people who come here and work hard.

“It’s a balanced and nuanced argument which is a mixture of no more something-for-nothing, control for immigration from outside the EU – but keep returning to the benefits that immigration can bring.”

One question has loomed over Cameron from the very start of the campaign, a question being asked even by some of his allies. If Brexit is such a whopping risk, what possessed him to take the gamble by promising this referendum in the first place? It is widely believed at Westminster that his chancellor and closest collaborator, George Osborne, thought it a crazy idea to make the pledge. “It was time for the British public to make this decision again,” Cameron insists. “This has dogged our politics for decades.” It has certainly riven his party for decades. “The fact that politicians have promised referendums and not delivered them has been corrosive and it was time to deal with it.”

Facebook Twitter Pinterest On Nigel Farage: ‘I’ve watched this guy for a decade – “Chinese people are Chinks, gay people are fags”, all the rest of it. He’s got a track record as long as your arm.’ Photograph: Andy Hall/The Observer

He cannot secure a vote for Remain without the support of people who may absolutely loathe him – supporters of Labour, the Nationalists, the Lib Dems and other non-Tories. Some would normally rather have their eyeballs stabbed with hot needles than follow the recommendation of a Tory prime minister. How does he appeal to them?

“I’d say this is not about one politician or one government, or protesting about issues you might be concerned about. It’s much bigger. I think they know they’re voting for a generation, for a lifetime.” He also invites them to look at the breadth of the cross-party support for continuing with membership. “It is a very, very big coalition of different people.”

He thinks that having all the major trades unions on the same side of the argument as a Tory prime minister ought to be very persuasive, and is clearly concerned that this is not getting through to voters because there has been so much media concentration on the personality battles between senior Conservatives. “Other parties and the trade unions are working very hard. Sometimes they can get squeezed out because, you know, the media love the sort of Dave and Boris show. That is a problem.”

He expresses anxiety that it has been “too much of an intra-Tory contest and that’s not good for the campaign”. This reflects worries among Remain strategists that non-Tory voters have been insufficiently engaged. So he is in the unfamiliar position of now wanting “to almost take myself out of the firing line so that Labour figures and others can have their say; I’m part of a huge coalition and I almost need to give those other parts of the coalition the chance to speak up because I mustn’t sort of hog it as prime minister”.

It is clear he wants more media attention for other advocates of Remain, especially Labour ones, because Labour votes are badly needed to win this referendum. “Look, even if you don’t agree with me, listen to the trades unions, listen to the Greens, listen to Jeremy Corbyn. And you can’t be accused of an establishment stitch-up if you’re saying listen to Jeremy Corbyn and the Green party.”

That is surely something he never thought he’d hear himself say: “Listen to Jeremy Corbyn.”

The argument about Europe has self-evidently shone stark illumination on the deep fissures within the Tory party, but it has arguably also highlighted something even more profound and disturbing: vivid and visceral fractures running through all of contemporary Britain. Between metropolitan and non-metropolitan Britain, between young and silver Britons, between doing-well Britain and the one that feels left behind, between a Britain that is basically comfortable with globalisation and another that feels an acute sense of identity loss.

He half accepts this. “We really need to explain that these opportunities are not simply for people who’ve already got advantage: these are opportunities for everyone.”

Facebook Twitter Pinterest On the campaign: ‘You can’t be accused of an Establishment stitch-up if you’re saying listen to the Green party.’ Photograph: Andy Hall/The Observer

Whichever way it goes, we suggest that such divisions will not simply disappear on 24 June. That he disputes. “I think the British electorate is very fair-minded. If the decision is made to stay, people will say, Inners and Outers will say, thank God that’s over. They’ll say: ‘fair contest, fair vote, we’ve decided, let’s got on with it’. I think we’ll be surprised by how quickly people come back together again.”

This strikes some of us as too insouciant about the high passions and deep divisions exposed by this referendum. Or perhaps we are asking too much of Cameron in seeking to get him to reflect on the healing that may be needed afterwards. In the fight of his life, with his country’s future and his historical reputation at stake, his mind has room to think only about the next 12 days.