Macron also used humor to defuse Le Pen's attacks. After a thinly veiled dig from Le Pen suggesting that the former banker would be beholden to financial lobbies if elected, Macron told her: "You'd be bored without me." While they were feisty, conservative candidate Francois Fillon was noticeably and unusually restrained. Once considered a leading contender to move into the presidency's Elysee Palace, Fillon's campaign has been badly hurt by accusations that his wife and children were paid with public money for jobs they allegedly did not do, which he denies. The ex-prime minister appeared weary and at times absent during the debate.

"I may have made mistakes. I have defects. Who doesn't? But I have experience," Fillon said.

Socialist candidate Benoit Hamon and far-left leader Jean-Luc Melenchon, both looking to boost their poll numbers, were the first to take swipes at Le Pen.

Hamon described Le Pen's attitude as "sickening" after she spoke of French schools as "a daily nightmare," so dangerous that pupils attend with "fear in their stomachs."Melenchon interrupted Le Pen as she was calling for boosted French-language teaching.

"How do you learn French, dear madam? By speaking it!" he said.

Of the 11 candidates in the election, only the five who are expected to be the largest vote-getters in the first round were included in the debate.

The first-round vote is set for April 23; the top two candidates go to the May 7 runoff.

AP