Asked how they want to create jobs in a country where the unemployment rate has for years hovered around 10 percent, Macron promoted pro-free market views, in contrast with Le Pen and her support for protectionism. For Melenchon supporters, it's Hamon and then Macron.
Socialist Party candidate Benoit Hamon, unlikely to get beyond the election's first round, mocked Le Pen for "playing the victim".
Le Pen and the Nationalists can be expected to play on the country's fear of Islamists and migrants following major terror attacks in January and November 2015.
When Le Pen, 48, replied that Macron was defending the European Union by reverting to "old classics" of 50 years ago about Europe's peace-keeping record, Macron retorted with a rare attack on her father, former far-right leader Jean-Marie Le Pen. But the race for the Elysee remains one of the most unpredictable in memory with twists and surprises in which some big players have been marginalised and scandal has tainted others.
A French prosecutor is investigating the activities of the far-right National Front on a regional council in northern France, a judicial source said on Tuesday after a newspaper reported a top party official was suspected of being paid for fake work. There is a shocking discrepancy here."It was unclear whether a final debate scheduled for April 20 would take place, after several of the leading candidates said it was being held too close to the election itself".
Le Pen seemed convincing only for 11% of the French, that in essence corresponds to her electoral base.
Le Pen denies wrongdoing.
Macron, whom the daily Le Parisien on Tuesday dubbed "the man to beat", has warned that commentators were still underestimating Le Pen.