Cameron will seek to reassure restive Tory activists by promising to foster "aspiration" and give school sport a £150 million cash boost.
The Prime Minister will will tell activists his approach chimes with the Tory values of highly-popular figures such as Margaret Thatcher and Winston Churchill as he attempts to steady the ship.
Addressing the party's spring forum after a turbulent fortnight following the disastrous Eastleigh by-election and a damaging bout of leadership speculation, he will say:
"The global race is not just about GDP.
"It's about saying to the mum who's worried about her children's future, we are building a country where there is a future, so your kids won't have to get on a plane to get on in life, they can make it right here in Britain.
"It's what this party's always been about - aspiration."
In a swipe at Labour opposition to tough benefit cuts being rolled out as part of the deficit reduction, he will paint them as "patronising people, patting them on the head and putting a benefit cheque in their hands".
Instead the government was "giving people the tools to succeed."
The speech comes just days before a Budget which is seen by MP and many party members - along with May's local elections - as a key test of his leadership.
Mr Cameron - who has come under fire from backbenchers over his "posh, male and white" inner circle - will acknowledge the "leg-ups" he enjoyed in life.
"I know the leg-ups I got in life. A loving family, wonderful parents, a great school and university.
"We want people to climb up through their own efforts, yes, but in order to climb up they need the ladder to be there in the first place, the family that nurtures them, the school that inspires them, the opportunities there for them.
"Great Conservatives down the generations have put those ladders in place. When Churchill invented the labour exchanges that helped people into work.
"When Macmillan built new homes. When Thatcher fired up enterprise so people could start their own businesses.
"That's what we're doing in the Conservative Party right now."
Mr Cameron will come under renewed pressure to abandon moves to legalise same-sex marriage - which opponents warn is leading activists to abandon the party in droves and is losing it large numbers of votes.
Several backbenchers spoke out today in support of the "Conservative Grassroots" group set up to campaign on the issue and for "core Conservatives values" in the wake of a major Commons rebuke to the premier on gay marriage.
More Conservative MPs voted against the legislation than in favour of the reform championed by Mr Cameron - 134 taking advantage of a free vote to voice their opposition.
The campaign group is holding an open meeting at the spring forum and released a video of messages of support from a number of MPs.
One, Peter Bone - a consistent critic of the leadership and vocal critic of gay marriage - said: "We have a real problem within the party and the leadership seem to be disconnected with the grassroots.
"It's an urgent requirement that the party reconnect - that the leadership, the backbenchers and members in the country are all united together. And I think that the leadership needs to act quickly to solve this problem."
Home Secretary Theresa May - who last week fuelled leadership ambition speculation with a speech which ranged far beyond her policy brief - is also addressing the forum.
She is reported to have been the target of Education Secretary Michael Gove's private warning to Tory Cabinet ministers earlier this week not to undermine David Cameron's position as PM.
Her speech is expected to be restricted to home affairs issues.
Health Secretary Jeremy Hunt and Communities Secretary Eric Pickles are also due to speak at the event in Central London.
Lord Coe said it is vital to target children at primary school in a bid to get them into a cycle of doing sport before it is too late.
"I think focusing on getting young people into patterns of activity, that we hope lead to a commitment to sport for life.
"You know, it's sobering, far too many young people are leaving primary school barely able to climb a flight of stairs.
"50% are leaving either obese or overweight. Getting the patterns of exercise early - those physical literacies in place - it's very difficult to claw that territory back when you start trying to think about it when they're 14 and 15, so getting those skill-sets in place and allowing the schools to be able to tap into good local provision if that is what is needed, I think will make a massive difference going forward," he told BBC Breakfast.