Conservative leader David Cameron is set to challenge Gordon Brown's vision for eradicating poverty.
David Cameron has Gordon Brown in his sights
Mr Cameron has already set up a social justice policy group as part of efforts to show his party has moved to the centre and is concerned about the poor.
He is due to make a speech stressing his desire to let charities and voluntary groups lead the fight.
And he will say Mr Brown, his expected rival at the next election, is wrong to say only the state can ensure fairness.
Ex-party leader Iain Duncan Smith is heading up the Tory policy group looking at how to help Britain's deprived communities.
It will look at the role of social entrepreneurs - small local groups of volunteers - in helping people out of poverty.
Mr Duncan Smith told BBC Radio 4's Today programme: "I hope the government, instead of sniping at this thing like children, will actually understand there is something fundamentally wrong out there, with kids trapped on drugs, on the streets, with kids leaving school early and families breaking down in real poverty."
He added: "It is a disaster in parts of Britain and it's time we dealt with it."
Social enterprise has been lauded by both Conservative and Labour politicians in recent months, although critics have questioned its ability to solve deep-seated social problems.
James Bartholomew, author of The Welfare State We're In, said: "I suspect its a feelgood phrase that's gone down well in focus groups. I do not really truly believe that this is a coherent policy plan."
But Mr Cameron is determined to show the Conservatives, and not just those on the political left, are interested in helping the poor and vulnerable. He will say both he and Mr Brown want to tackle poverty but confront head on the chancellor's thesis on how to do it.
"We have radically different solutions to the entrenched problems of multiple deprivation, and the root causes of poverty in Britain today," he will say.
"On the one hand, we can see top-down, centralised schemes from an outdated Labour approach that means well but fails badly.
"On the other, a forward-looking vision which recognises that social justice will only be delivered by empowering people to fulfil their potential.
"Our approach: trusting people and sharing responsibility. Or Gordon Brown's approach: creating dependency and removing responsibility."
Mr Cameron wants to harness the work of charities, for example, by creating "social enterprise zones" where voluntary groups encounter less "red tape".
Mr Brown has also backed social enterprise but has argued it cannot guarantee fairness in the same way government can.
Mr Cameron has backed some of Tony Blair's reforms, including plans to offer more choice in schools.
But he is increasingly trying to show the gap between him and Mr Brown, who is expected to replace Mr Blair in Downing Street before the next election.
The Tory leader recently made a personal attack on the chancellor, calling him a "creature of the past".
"Gordon Brown is the old-style thump-thump-thump and I think that's exactly what turns people off," he told the Sunday Times last month
"I find (him) awful because it's just like listening to a speak-your-weight machine on propaganda."
Mr Brown on Tuesday urged people to judge Labour on its record.
He told GMTV: "I think when people look back over the last eight years, they do know that we have created stability in the economy and we are trying to build on that."
Last weekend Mr Brown laid out what many saw as part of his agenda for a potential premiership.
Portraying Labour as a modern patriotic party, he suggested Britain should have a day to celebrate its national identity.