PARIS - French President Nicolas Sarkozy made a last-ditch appeal to far-right voters on Thursday after failing to land a knockout blow in a heated televised debate with Socialist rival Francois Hollande before Sunday's decisive runoff.

Hollande, ahead in opinion polls by six to 10 points, was calm and unflappable during the nearly three-hour debate on Wednesday while the conservative Sarkozy, struggling to catch up with the moderate social democrat, was often agitated and tense.

Commentators said the confrontation, watched by 17.8 million people out of an electorate of 44.5 million, was no game-changer and probably only reinforced voters' opinions in a contest that has been as much about style and personality as substance.

"It was a draw but as Mr Hollande started as favorite, he remains the favorite," wrote Francoise Fressoz in an editorial in Le Monde. "Mr Sarkozy did not manage to destabilize him, which was his objective from the start."

Returning to the airwaves on Thursday in a bid to convince waverers before campaigning ends at midnight on Friday, Sarkozy appealed to the nearly one-fifth of voters who cast their ballot for the National Front in the April 22 first round.

"The opinion polls are lying. An election has never been this open ... It's even more open after the debate," Sarkozy told RTL radio.

"I want to speak directly to National Front voters. Who would benefit if you cast a blank vote? It would benefit Hollande, the regularization of (illegal) immigrants, crazy overspending."

Television commentators said Sarkozy had performed "like a boxer" in Wednesday's debate and Hollande "like a judo fighter," using flashes of wit and interjections to unbalance his rival.

"Hollande presides over the debate," left-wing Liberation wrote on its front page, while the right-leaning Le Figaro, with a headline "High Tension", emphasized the bitterness of the exchanges. It noted that every euro zone leader to seek re-election since 2008 had lost, but said divisions in the French left and Hollande's outdated policies gave Sarkozy a chance.

Hollande, 57, was confident and relaxed in the early exchanges of Wednesday's contest, saying he aimed to be "the president of justice" and "the president of unity".

He said Sarkozy, also 57 and in office since 2007, had divided the French people and was using the global economic crisis as an excuse for broken promises. "With you it's very simple: it's never your fault," Hollande said.

Sarkozy, fighting for his political life, repeatedly accused his opponent of lying about economic figures and reeled off reams of statistics in an attempt to swamp his adversary.

Deriding Hollande's pledge to be a "normal president", the president said: "Your normality is not up to the challenge."

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