As Hollande stated, the vote was a victory not only for him but also for the French left. Extensive media coverage, a high turnout of 2.7 million voters and a decisive result will give the socialist candidate greater democratic legitimacy and momentum. An incredible 6 million viewers watched the final TV debate on Sunday between Hollande and the runner-up, Martine Aubry.
Known by some as the Iron Lady of French politics (albeit on the left), Aubry was gracious in defeat and immediately called for the party to unite after the primaries. Supporters were singing football and rugby-inspired songs, repeating the slogan "tous ensemble, tous ensemble (all together)" outside the Party's headquarters on the Rive Gauche.
Open primaries were initially suggested by a progressive think tank, Terra Nova, and encouraged by a few reformist leaders with a modernising agenda. Opening up the selection of the Party's candidate, they argued, meant fully embracing twenty-first century politics and would force the Parti Socialiste to go beyond its organisational structure and address the concerns of society as a whole.
Political differences seemed to emerge between the two finalists between the first and second rounds. Aubry was portrayed as the traditionalist left-winger and Hollande the centre-left moderniser. But Martine et François have a lot in common. They are from the same generation, in their 50s. She is the biological daughter and he the spiritual son of Jacque Delors, the former President of the European Commission, and the two of them worked closely with Lionel Jospin. They both attended the Ecole Nationale d'Administration, the elite institution that trains senior public servants. There are a few differences in policy emphasis, but what distinguishes them mostly is their style and personality.
Essentially, Hollande won because he is seen as the candidate best placed to beat Nicolas Sarkozy. He is an impressive orator, a steady and calm figure compared to the hyperactive, petulant President. But will this be enough for the PS to finally return to power next year?
Three million voters took part in the primaries, but 20 million are needed to ensure the victory of the left next year. The French socialists haven't won a Presidential election since the re-election of François Miterrand in 1988. Their last whiff of power came to an abrupt end when the incumbent Prime Minister, Lionel Jospin, failed to get through to the second round in the Presidential elections in 2002. Being beaten into third place by the National Front's Jean-Marie Le Pen is a deep scar in the French socialists' collective consciousness.
Perhaps the left's successive defeats will help Hollande keep the traditionally fractious PS unified. He will probably make use of the defeated primaries candidates during the campaign to show that he is a leader willing to unite and use the talents of his party. The overwhelming feeling within the Party is that unity has to be now or never. The party machine is therefore ready for the battle, with an enlarged army and a solid programme.
In the most recent poll, Hollande is at 63 per cent, with Sarkozy on 38 per cent. But the socialists can't take anything for granted. The President is trying to tone down his hyperactive personality and appear more presidential. The recent arrival of his baby with Carla Bruni will probably give him a bounce in polls.
The media attention and the turnout during the primaries are clearly cause for concern for the French right. Ministers and MPs from the governmental majority -- and even Sarkozy -- successively raised legal concerns, expressed exasperation about the intense media coverage, criticized the candidates and their programmes, but, in the end, proved unable to deal a blow to the left's new found democratic legitimacy.
The right is angry, the left is determined.
Determined to win the Presidential elections for the first time in over two decades.
The primaries were an effective prelude. Now the real battle commences.
Emma Reynolds is the Labour MP for Wolverhampton North East and Shadow Minister for Europe.
Axelle Lemaire is the French Socialist candidate for next year's French parliamentary elections for the new constituency of Northern Europe.