Andy Burnham is one of that rare breed – a conviction politician whose politics have been shaped by his life experiences. During this campaign his integrity, campaigning skills and focus on policy has convinced me and thousands of others that he is Labour’s best choice for leader.

In analysing who should be Labour’s next leader, I think we need someone with a credible economic alternative to the coalition’s ideologically-driven public spending cuts. Andy has taken the most credible and comprehensive approach on how to reshape Britain’s economy. His proposed National Credit Union is a way of decentralising economic power and rooting it in the hands of individuals and their communities. He takes seriously the need to cut the deficit through innovative taxes and efficiency savings but, above all, through generating sustained economic growth. Andy is the person to implement Labour’s alternative economic strategy.

But we also need someone who can take back middle-England, and also appeal to the people in seats ranging from historical marginals such as Basildon and Hastings to traditionally safe seats such as Manchester Withington and Hornsey and Wood Green who voted Labour consistently in the 1990s and 2001, but who deserted us in 2005 and 2010 because they felt we had become out of touch. Of all the candidates, Andy Burnham is the one who can reclaim these voters.

But don’t take my word for it. In a Newsnight focus group last week of disaffected Labour voters from the south, Andy swept the board, winning nearly 60 per cent of their support. There is, of course, a danger (as we found out in government) in drawing too much from focus groups, but it clearly demonstrated that Andy has the greatest potential to re-claim the southern marginals which we need to take back if we are to win another general election.

However, there’s no point in winning if you have to jettison your principles to do so. And, the main reason I am backing Andy is because of policy. He has produced plenty of bold ideas and he is passionate about them because they come from the heart. Andy’s ‘Aspirational Socialism’ manifesto is the most detailed policy document of any candidate. I don’t agree with all of it, but it’s difficult not to admire the sheer integrity of a candidate setting their political stall out like that.

His proposals to establish a National Care Service would be an integral part of a modern NHS. Meanwhile, on taxation, his campaign to replace two desperately regressive taxes that particularly hurt young families and individuals, council tax and stamp duty, with a land value tax, that would mean that those living in properties worth between £100,000 and £200,000 would no longer be paying 40 per cent or 50 per cent of the tax paid by property millionaires, is the most radical and progressive tax policy by a senior Labour politician for decades.

Like me, Andy is not interested in debates about ‘new’ or ‘old’ Labour. The past is precisely that – there is no point in defining ourselves by labels that are 15 years old. The political landscape has changed since the 1990s. We have to learn from the successes of our 13 years in government – transforming the NHS, our schools and public services – but also from our mistakes. We did not lose in May because we ditched ‘new Labour’. We lost because our party in government had become tired, out of touch and didn’t seem to offer anything new. It had become obsessed with constant political triangulation, backbiting and a ‘top-down’ style that alienated party members.

I will make one plea. Labour has had four governments since the second world war – Attlee, Wilson, Wilson/Callaghan and Blair/Brown. After our defeats in 1951 and 1979, the party was ripped apart by infighting, particularly in the early 1980s. We must be clear that regardless of who we vote for, the most important thing is that whoever we elect becomes the next prime minister – parties that go in for self-indulgent infighting lose elections. We are now a natural party of government. I saw that at Progress conference back in May. The mood was upbeat. We knew we had lost badly, but the sense of optimism that we could bounce back quickly and learn from our mistakes was palpable. I believe that Andy Burnham is the person to help Labour do this and lead the ‘people’s party’ back to power.

Ben Fox is political adviser to the socialist vice-chairman of the economic and monetary affairs committee in the European parliament, and chairman of GMB Brussels