The atmosphere was feverish as dozens of Socialist Party supporters gathered last night in a well-heeled district of south Paris to listen to the presidential debate.

They cheered as Ségolène Royal attacked Nicolas Sarkozy, booed as he defended himself and groaned as he demanded precise facts and figures from her.

But on an old blue sofa in a corner of the theatre hired by the party, Matthieu Gaulet bit the edge of a plastic cup in silence.

“She’s too aggressive,” said the 22-year-old floating voter, who was accompanying Socialist friends. “I don’t know whether I’ll vote on Sunday and I’m not sure whether this debate is doing anything to convince me to do so.”

He slumped back down and threw back his head as he listened to an antagonistic exchange over the financing of the French state pension system.

“Frankly, this is not very interesting,” Mr Gaulet said.

“They are both boring me.” No one else in the cramped, overheated theatre dared to voice similar opinions. “I think Ségolène Royal is good,” said Lucie Berges, a 25-year-old law student. “She is relaxed and on the attack. It’s going well.”

Civil servant Valérie Vauquelin, 39, agreed. “She is really audacious and I admire her.”

But behind the facade lay a concern that became increasingly tangible as the evening wore on: Ms Royal’s supporters praised her for resisting and landing some punches, but not the knockout blow that they said she needed.

Some even admitted that Mr Sarkozy, seeking throughout to appear calm and in control of his notoriously jumpy nerves, had got the better of her.

François Stofft, a 47-year-old aeronautical engineer said: “Sarkozy is very cunning. He has been pinching her ideas and vocabulary all the way. He’s mastering his nerves rather better than she is.”

Mr Stofft had been hoping that the centre-right candidate would blunder. But after an hour of heated exchanges, that hope was fading.

Suddenly a huge cheer went up when Ms Royal launched a violent attack on her adversary, accusing him of immorality over his policy on handicapped children.

But the cheer swiftly died away as Mr Sarkozy neatly side-stepped with a counter accusation that she had lost her nerves. “He scored a point,” a middle-aged man said.

François Gausegonzac, a 61-year-old pensioner, said: “Sarkozy is not doing too badly and I have to say that she has not managed to destabilise him.

“After the first round of the election I was almost certain that Sarkozy would win; now I am a little more optimistic but the opinion polls have not moved in our favour and I am not sure this debate will change very much.”

Thierry Currivand, 45, a management consultant, felt that Ms Royal had begun badly. “She was tense and she obviously had stage fright.” He agreed that Mrs Royal had appeared aggressive but said that she had also seemed natural. And that might touch voters.

Could Ms Royal win on Sunday? Mr Currivand reflected: “It would be a surprise, a very big surprise but, you know, the French rugby team is never as good as when everyone expects it to lose. The same thing is true of voters in this country. They like producing surprises.”

Calm? I am!

Sarkozy “Calm down, don’t point at me with your finger like that”
Royal “No, I won’t calm down”
Sarkozy “To be president you have to be calm”
Royal “Not when there is injustice. There is anger that is perfectly healthy . . . I won’t allow the immorality of political speeches to gain the upper hand”
Sarkozy “I don’t know why Madame Royal, who is usually calm, has lost her cool”
Royal “I have not lost my cool, I’m angry. It’s not the same. Don’t be contemptuous”
Sarkozy “I am not calling into question your sincerity, Madame Royal. Don’t call into question my morality. And with that, Madame, the dignity of the presidential debate will be preserved”

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