Hollande is on course to unseat right-wing incumbent President Nicolas Sarkozy in the poll to choose the powerful leader of the eurozone's second economy, which will be conducted over two rounds on April 22nd and May 6th.
With eurozone bond markets on edge over renewed fears that Spain and Italy will struggle to cope with their sovereign debt, Sarkozy has warned that France would be next in the firing line in the event of a Socialist victory.
But Hollande hit back hard, accusing Sarkozy of racking up debt and of allowing France to be bullied by the world of finance into sacrificing growth for austerity, without reaping any benefits for the real economy.
He said he would fight "speculation" and work with France's EU partners to better regulate markets, rather that surrendering to them, as he alleged Sarkozy has done since his election in 2007.
"What I want is for us to show, France but also Europe, that we have a shared capacity to dominate finance," Hollande said, on public television.
"I've said very clearly what would be my path towards the repair of our public finances. I've said that we need more growth, because it is needed, and so I need fear no crisis," he declared.
"And if the markets are worried -- I don't know if they are, I know that for now they are unfortunately mobilised as regards Italy and Spain -- I will tell them here and now that I will leave them no space to act," he said.
And he dismissed fears his election would trigger a speculative attack on the euro, noting that he has been the opinion poll frontrunner for months and so the markets have had time to get used to the idea of him as president.
"It's the outgoing president who brought the country to the situation it is in. Public debt has grown by 600 billion euros, we've lost our Triple-A credit rating and we have a trade deficit of 70 billion euros," he said.
"And now he comes to tell us: 'Watch out, it could be even worse if someone else was in charge'? Well, no it couldn't."
Countries borrow money on international bond markets to finance their budget deficits and to rollover their debt. If they lose the confidence of investors, the interest rate to borrow can rise to unsustainable levels, forcing a government in trouble to seek rescue help elsewhere.