All politicians claim to have the common touch, yet much of the Labour leadership contest has been dominated by a debate over which of the five candidates – if any – has at least one foot in the real world. Ed Balls insists he has. Several hours before we met in a café near Bristol Temple Meads station, he began his day on the campaign trail meeting, and playing the drums with, Daniel Evans, a 15-year-old Asperger's campaigner, who has become a pen pal since he first wrote to the Labour government about his condition. A YouTube video has done the Balls campaign's street cred no harm at all.
By contrast, the Milibands – Ed and David – stand accused of being policy wonks who have become barely proficient in "speaking human". Mr Balls warns if Labour chooses either of his main rivals as leader, the party risks repeating the mistakes of the general election leader debates, in which, he says, Messrs Brown, Cameron and Clegg "sounded as if they weren't in touch or sounded as if they were reading out somebody else's script".
Whereas Mr Balls, of course, can talk to just about anyone: "I chaired the world finance ministers' deputies for two years. But I can also go into a Sure Start children's centre with a group of mums and dads and talk to them about their kids in a way which doesn't make them feel somebody has just arrived from Mars." Echoes, perhaps, of Mr Cameron's jibe that the wannabe Labour leaders look like "a Star Trek convention".
Mr Balls believes he has had "more substance on policy" and while his opponents have been "talking a party narrative" he claims to articulate the everyday concerns of normal people, who ask: "Why has my daughter been waiting for two years for a house; and I'm worried that tuition fees are making it harder for my kids to go to university; and I'm really worried about what public service cuts will mean. And why can't Labour set out an alternative view, or isn't there one?"
The early stages of the contest were dominated, he believes, by the "convenient, personality-driven narrative" story of the Milibrothers going head to head. As a result he found it "hard" to break through because "everybody was looking backwards". "If you are the features editor on a Saturday, the Cain and Abel story is easier to lay out on the page."
Mr Balls admits the retro-focus counted against him, with the negative impact of his close association with Gordon Brown – as one-time henchman, adviser, spin-doctor and, later, minister. He tackles the issue head on. "I don't think it matters a jot to be honest. As I have said, Ed Miliband was working for Gordon when I arrived in 1993, and he wrote the  manifesto."
He has spoken to Mr Brown "a few times" during the leadership contest, but has not asked for tips on how to win. "Gordon is grown up about this and so am I. He lost the election. Didn't connect on the doorstep. People didn't say: 'I want Gordon Brown to carry on'. He made some bad calls. That's a fact." Still loyal to the former PM, Mr Balls believes "history will judge him well", especially on policies to save lives around the world. He also says, after some thought, that Mr Brown should appear at the party's conference in Manchester in two weeks. "We are moving from the past to the future and we should do that in a dignified and united way."
There have been reports that David Miliband has the backing of Mr Blair, while Ed is supported privately by Mr Brown. "I don't think it matters," Mr Balls insists, noting his supporters are those on the up and likely to be ministers of the future, including his wife, Yvette Cooper, the party's Work and Pensions spokesman.
He is convincingly relaxed about the idea that Ms Cooper might yet land the shadow chancellorship – "I think Yvette is very talented" – and insists he is not positioning for the role himself. Amazingly, he even denies hankering after the Chancellorship in government, claiming Mr Brown and Lord Mandelson were keener.
"In the end, there are certain things you learn in life. One of which is never ever to spend your whole time thinking about a job you haven't got." Is this a thinly veiled reference to a decade at Mr Brown's side, plotting to oust Mr Blair? "Let's just say it's an experience I've got. I want to enjoy every day. I want to be leader of the Labour Party, but if not, I'll enjoy and be honoured to do whatever I do in the next few years."
Mr Balls suggests the Miliband brothers in particular have become "a bit stuck" in a "sterile" debate, fighting an old battle which dates from the Brown-Blair era, of which he was a key player himself. Despite some commentators composing their fantasy leader with the attributes of each of the candidates, Mr Balls believes he is the "most complete".
Targeted heavily by the Tories in his Morley and Outwood seat during the general election, he says the experience has made him stronger: "I'm a much more hardened campaign politician than any other candidates now, because I know what it's like on the night of the election not knowing whether you're going to give your winning or your losing speech."
His battle to overcome a life-long stammer – in the Commons chamber and in front of TV cameras – has added to his resilience. With his wife, he was also placed at the centre of a inquiry into their expense claims. They were cleared, but not without a sustained campaign from parts of the media determined to prove wrongdoing.
"Anybody who writes me off makes a big mistake. Nothing David Cameron can ever say to me would knock me down; there is nothing the Daily Mail could do to me which could ever knock me down."
The new Labour leader cannot have policy dictated by the house magazine of Middle England, he adds. "Blunting your message and looking like David Cameron is not going to win us the next election. Being clear about what we're about – even if that ruffles some feathers – I think is vital. I'm not going to stop doing that." Mr Balls warns his rivals lack the economic competence to win the coming battle over spending cuts.
Last month, he gave a major speech at Bloomberg, setting out his economic case, based on a Keynesian vision of investing in public works to boost growth. He has advocated using a £6bn underspend from government borrowing to build 100,000 houses, creating three quarters of a million jobs.
"The public wants us to cut waste but they don't want us to cancel their new schools. They want us to get the deficit down but not if it risks hundreds of thousands of jobs in the private construction sector."
This is the central argument to his economic pitch. He is particularly pleased to claim the support of both Ken Livingstone and Boris Johnson for his argument against the coalition's draconian cuts programme. "It is an unlikely alliance. The lesson of history for Labour is that if we don't have the confidence and the credibility to stake out a view and instead run along with the consensus, then we end up not having any distinction."
Since the move into opposition, Mr Balls' stock has risen after taking the fight to Secretary of State for Education Michael Gove, not least for the bungled cancellation of the Building Schools for the Future programme. He claims Mr Gove has been "exposed", because in opposition he was good at "writing a 900-word sketch which was funny ... but government is about the actions you take". Mr Balls says his success has been a combination of "relentless" opposition and Mr Gove "running ahead of himself, thinking he could move fast: quick legislation, big cuts, when he hadn't done the work and thought it through".
There is no love lost between the pair. "I have never been the kind of politician who at the end of the afternoon slaps an opponent on the back and says, 'Let's go off for a Pimm's'. That's not how I have ever done it." There is respect, but they are not "mates". "Michael Gove has always been personal about me; I have never responded in kind. That's not how I have done politics." Apart from occasional jibes at leadership opponents, obviously.
Ed Miliband has made the case that the Lib Dems are the weak link in the coalition which must be targeted, a tactic Mr Balls claims is "very dangerous" and will "let the Conservatives off the hook". "On the economy and public service winning the argument with David Cameron and George Osborne is more important than discomforting the Liberal Democrats," he adds.
Despite his reputation as a bruiser, Mr Balls denies ever getting annoyed. Only two things have angered him during the campaign – Costa Coffee's limited range of toasted sandwiches at motorway services, and occasions when work clashes with his family commitments. He has gone without seeing his three children – Ellie, Joe and Maddy – for several days at a time, though he cleared the diary for his daughter's first day at secondary school: "You don't want to look back and wish you'd got a better balance."
Motoring around the country in the back of his campaign-branded Ford Galaxy, the self-confessed karaoke addict has relaxed listening to school disco classics on the iPod of former minister and campaign manager Lord Knight. The recent glut of political memoirs remain unread, and will "gather dust" until next August at the earliest. Instead, he has been reading the Twilight series, because his daughter is. Even in the long hours on the road he has not started drawing up his fantasy shadow cabinet – aside from his praise for his wife – or thought about writing a leader's conference speech, though it is believed Ed Miliband has.
An appointment with a hostile Newsnight panel awaits. Time is almost up. Right on cue, an 11-year-old girl in her new school uniform approaches nervously to ask for an autograph. He asks about school dinners and finding her way around the school. She goes away with not one but two signatures. Her mum chuffed to bits. The message is clear: Man of the People. If only Labour members were so easy to win over.
Curriculum Vitae: A life in politics
1967: Born in Norwich. His father is a zoologist
1972: Attends Bawburgh Primary School, Norwich, and later Crossdale Drive Primary School in Nottinghamshire
1978: Goes to the private, all-boys Nottingham High School
1983: Joins the Labour Party
1985: Reads philosophy, politics and economics at Keble College, Oxford. Obtains first class honours.
1989: Kennedy scholar at Harvard University
1990-94: Joins the Financial Times, becoming a columnist and leader writer
1994: Appointed economic adviser to the shadow chancellor, Gordon Brown. He is credited with convincing Brown to publicly endorse 'post-neoclassical growth theory' prompting Michael Heseltine's famous comment: 'It's not Brown's: It's Balls''
1998: Marries Yvette Cooper, above, now a fellow Labour MP and the party's Work and Pensions spokeswoman. They have three children
1999-2004: Appointed chief economic adviser to the Treasury, working as Brown's right-hand man. In that role he is described as 'the most powerful unelected man in Britain'
2005: Elected as MP for Normanton
2006: Promoted to economic secretary to the Treasury
2007: Joins the Cabinet as Secretary of State for Children, Schools and Families when Brown becomes Prime Minister
2010: Avoids a 'Portillo moment' when he is re-elected in the newly formed Morley and Outwood constituency by a margin of 1,101 votes, seeing off a Tory decapitation strategy
19 May 2010: Declares himself a contender for the leadership of the Labour PartyReuse content