Do you want to be leader? The question Miliband can't escape

The first person this week to ask the Foreign Secretary whether he sees himself as a future leader of the Labour Party was 17-year-old politics student Danny Hopes. Because the question was framed in politely hypothetical terms, David Miliband batted it away with his standard answer that if you think about another job you won't succeed at the one you've got.

But the timing of Danny's question, at a lively Q&A session in the chapel at St Mary's Catholic College in Blackpool, was apposite. When it was put to Mr Miliband that Nick Clegg was now suggesting he might do a deal with Labour even if it came third in vote share, provided Mr Brown was not leader, the Foreign Secretary was emphatic. "It's not for Nick Clegg to choose the leader of our party. We have a strong leader, strong team and strong programme," he told The Independent. "If he wants to [play] fantasy cabinets that's his choice... My job is to focus on my performance as Foreign Secretary. I want to be a successful Foreign Secretary in a re-elected Labour government."

But in the back of his armoured Foreign Office Jaguar between Lancaster and Blackpool Mr Miliband also added: "I don't believe we'll come third – it's something at odds with my sense of how the votes will come down at the end. I just don't think that will be the outcome. So all the commentary – mainly by Clegg and Cameron – about what's going to happen in those circumstances, is a complete waste of time. We have no intention of coming third. We are trying to win the campaign. We are determined to win the campaign."

Mr Miliband shows every sign of doing his best to ensure that happens. He had arrived the evening before in time for some intensive door-knocking in the marginal Lancaster constituency, and seemed to be enjoying himself.

At St Mary's he reminisced about his late father, the Marxist writer and theorist Ralph Miliband, for the benefit of Rhiannon Evans, who is studying for her history A-level. On the day he was demobbed from the Royal Navy, ahead of the post-war election which swept Clement Attlee to power in 1945, Chief Petty Officer Miliband was told crisply by his commanding officer: "Well, goodbye, Miliband. Don't vote Labour."

For a man sometimes seen as the most cerebral, even wonkish, member of the Cabinet, Mr Miliband, who has two adopted sons, had an easy way with the toddlers at the YMCA nursery in Fleetwood, engaging with one four-year-old girl on the vexed question of who is the fourth member of the Wiggles, the Australian singing group for children. He – and she – could only remember three: Anthony, Murray and Jeff. "We'll have to Google it," announces the Foreign Secretary, finally giving up.

On the road, Mr Miliband rejects persistent attempts to draw him into the discussion of post-election deals which has dominated the dialogue between the other two main parties this week. "A hung parliament is not on the ballot paper," he says. "People feel cheated by the expenses scandal and they are going to feel doubly cheated if they get to the end of the election and they are none the wiser about what the different policies of the parties are... The other two parties are attacking the political game but actually playing it, which is why it's right that from the Prime Minister down we are talking why people should vote Labour."

Saying the Tories are "running against a party which doesn't exist – a hung parliament party", he adds: "The Cameron wrapper on the old Tory product doesn't change the producer and when it comes to the [Liberal Democrats] people can see the difference between someone who can win the [TV] debates and someone who can run the country... It is a ruse to avoid any difficult discussion about what they would do in government."

But hadn't his colleague Alan Johnson himself fuelled the debate by saying there was no reason to fear a hung parliament? "Alan is fighting like hell for a Labour victory. You can have Alan Johnson or Chris Grayling as Home Secretary. Need I say more?"

To underline his point on policy, he adds that the Tory theme of the "Big Society" is "born of marketing because the Tories think they have to say they're not against society pace Mrs Thatcher, but underneath the wrapper... their deeply reactionary view on the future of Britain is one in which the strong are able to fend for themselves and the weak are left to sink."

But aren't there many cases where, say, parents on their own initiative do indeed run successful, self-financing, social projects like after-school clubs? Very much so, says Mr Miliband, and they are likely to be based, for example, on state premises like schools which are open from 8am to 10pm "with really good facilities". He adds: "The idea that this group is going to thrive if the government reins back on what it provides is fantasy.

"What will happen is that the voluntary sector will become a source of charity for the poor instead of a source of dynamism for the country. There are three legs of the stool: strong government, regulated markets and dynamic civil society. If one leg is shorter than the other then the stool falls over."

He adds: "More people are volunteering in Britain than ever before." And that, says Mr Miliband, gives the lie to the idea that the "big state" stifles such activity. "Cameron says that big government is the source of our problems. He also says he wants to defend the NHS, the largest employer in the world, and put a moratorium on any changes to it."

Pointing to tonight's final TV debate, Mr Miliband says it is "extraordinary that there hasn't been a question on the NHS in the first two debates. It would be a democratic farce to end the debates without a discussion of the NHS because it's an emblem of what Labour has changed about Britain and a national social care service is an emblem of what needs to be done next."

Mr Miliband is also scathing about the "broken society" charge to which Mr Cameron returned on Tuesday. "The Tories on the one hand try to convince the country that they're the party of hope and ideas, but actually they spend most of the time spreading fear, telling everyone that the country is broken.

"Britain has some broken families ... but it is not a broken country. The Tories tore up the social fabric and we have spent 13 years putting it back together, from cutting crime to helping pensioners and rebuilding social housing. Is it perfect? No, of course not. The lesson of 13 years of progressive politics is that people's expectations are always ahead of what we can deliver, and rightly so. But Government makes more impact over the medium term than people expect. Go to any city in Britain and you see a fundamental change of expectations as well as reality."

Yet wasn't it Labour that was trailing in the polls? "I have been saying that it's always hard to win a fourth election. It should be hard. If it was easy there would be something very wrong with the democratic process.

"A governing party that's been in for 13 years should be tested hard. It's completely understandable that the voters will think hard but I think they will come back to Labour. I think it's a Labour moment in the sense that the problems of market failure, of social inequality, of international insecurity and instability, demand a progressive response."