Sajid Javid has promised to break from the austerity of the last nine years by slowing the pace of debt reduction to fund a multi-billion-pound spending spree.
The Home Secretary said the move would still involve debt coming down but could free up to £25 billion a year for spending priorities, including a funding boost for education.
Mr Javid also said he had “done my homework” on Brexit, insisting that a technological solution to the Irish border problem could be found – with the UK paying hundreds of millions of pounds to fund it.
The Tory leadership hopeful told Sky News’ Sophy Ridge On Sunday: “I want to see a multi-year, multibillion-pound boost in investment and spending in schools, and really change the life chances of so many young people.”
He said the austerity programme set out by George Osborne and Philip Hammond in Number 11 had been “the right policy for that time” but more money was now needed for services.
“What I would do is slow down the rate of debt reduction, government debt reduction as a proportion of GDP.”
He said that could free between £15 billion and £25 billion a year, some of which would go to the education system, with other money going to local government and efforts to tackle crime.
Mr Javid has been endorsed by Scotland Conservative leader Ruth Davidson who said he is the "man for the job".
Mr Javid, the son of a Pakistani bus driver, has a background which is in stark contrast to rivals including Old Etonian Boris Johnson.
At school it was recommended that he should be a TV repairman.
“I was told that I couldn’t study maths at O-level so I had to get my dad to pay for it.
“I was told that I could only study two A-levels when I was told that you had to have three to go to university, so I had to change schools and go to a local college.
“But these are struggles I don’t want other people to have.”
He added: “I think the country, not just the Conservative Party, is ready for leaders – including in politics and we have seen in other walks of life – from all sorts of backgrounds.”
He said he was an outsider in the party both because of his race and his background but “sometimes there’s a strong case to have an outsider to actually become a leader to shake things up”.
On Brexit, Mr Javid insisted he could succeed where Mrs May had failed, despite warnings that no technological solution to the Irish border was available and Brussels’ refusal to put a time limit on the “insurance policy” of the backstop.
“You don’t need a magic solution for this, the solution exists. We’ve done the homework on this,” the Home Secretary, who has ministerial responsibility for the UK’s borders, said.
“I will change the dynamic and I will do that by offering the money to pay for the border.
“It is justified that we do that because, economically, if that unlocks a deal we will have a mini economic boom in this country if we get a deal and that will pay for that.”
He said the policy of a Javid administration would be to leave the EU on October 31 and “if I have to choose between no deal and no Brexit, I would pick no deal”.
The Home Secretary also waded into the drug debate, after Michael Gove's revelation he "deeply regrets" taking cocaine on "several occasions 20 years ago."
The Environment Secretary admitted to taking the Class A drug during an interview with the Daily Mail, but said it was a "mistake."
Mr Javid said he has never done drugs and criticised middle-class drug users who should be "thinking about the impact they are having."
He said: "Anyone that takes Class A drugs, they need to think about that supply chain that comes from Colombia to let's say to Chelsea, and the number of lives that are destroyed along the way.
"They have their organic food, they boast about buying fair trade, they talk about climate change, and at the same time, come Friday or Saturday night, they're all doing Class A drugs."