The theme of Labour's annual conference in Liverpool this coming week will be "responsibility", as Ed Miliband begins trying to explain why he should become Prime Minister.

Miliband has looked impressive recently, speaking out against phone hacking and calling for an inquiry into the riots - a demand the Coalition more or less acceded to.

What he still hasn't done is set out why he's a potential prime minister, rather than just a decent fellow.

This is partly a deliberate decision. Upon becoming leader 12 months ago, he ordered Liam Byrne, Labour's Shadow Work and Pensions Secretary, to undertake a thorough policy review.

It meant, until now, that he was vulnerable to the charge that he didn't actually have any policies. Instead, as he said himself, he had "a blank sheet of paper" waiting to be filled.

But Liverpool is where all that changes.

Delegates will be confronted with the results of a year-long policy review which has involved consulting more than a million people, with the findings published in four reports.

These will focus on:

1. The squeezed middle. The idea that working people are seeing their standards of living eroded as a result of inflation and pay freezes, and want a government that will stand up for them. Labour must not allow itself to be seen as the party which cares about the poor and benefit claimants, and takes the middle classes (working people on average incomes) for granted.
2. The British promise. Previous generations assumed their children would enjoy a living standard higher than they did. Today, parents and grandparents worry that their children will be poorer and more indebted than them.
3. Responsibility. This is a theme of all the policy reviews, but also gets a report to itself. People want a government that rewards responsibility and opposes the irresponsible, from benefit claimants who are capable of working to rich bankers collecting massive bonuses.
4. Britain's place in the world. I don't have much information about this one, although I would guess it focuses on foreign affairs and overseas aid.

For some of the Labour faithful, this is going to be challenging. They may have imagined that the death of "New Labour", with a discredited Tony Blair off in Jerusalem and puppetmaster Peter Mandelson out of the picture, would have seen the party returning to red-blooded socialism.

But the message of the policy review will be that elections are won from the centre - and that's where Labour must be.

So, for example, it will suggest that the benefit system is reformed to create a safety net for those who have actually paid in to it - rewarding responsibility - rather than simply rewarding each according to their needs.

Somebody who has worked and paid taxes and then loses their job might find their benefit payments are significantly higher than payments offered to someone who has never worked, under this system.

The review will also conclude that Labour must listen to people's concerns about immigration - and act on them, not just pay lip service.

To some of Labour's core supporters, this will sound like a lurch to the right, rather than a move to the centre. But Mr Miliband will never succeed in taking Labour back to power if he listens to them.

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