Since the February 6 assassination of opposition politician Chokri Belaid, world media coverage of Tunisia has focused mostly on the polarisation between Islamist and secular forces.
Many on the secular side blame Ennahda, the ruling Islamist party, for Belaid's death, even though party leaders have condemned the incident and officials have arrested several young Salafis in connection with the crime.
Yet it is actually not the secularist-Islamist battle but another division, increasingly visible over the past months, that needs to be watched closely if one is to understand which path Tunisia's revolution is likely to take: tensions are growing between Ennahda and the ultraconservative Salafi movement. This is particularly evident in their competition to win the allegiance of Islamist youth.
The number of ultraconservatives, though still low, is increasing in a country long hailed for its moderate "Tunisian Islam" interpretation of the faith. Religiously-motivated violence has also been steadily on the rise since the Tunisian revolution. Only last week, security forces clashed with Salafi jihadis in the mountainous area close to the Algerian border.
The recruitment of young Tunisians has become a central tool for the Salafis. To the distress of the Ennahda movement, Islamist youth seems to be particularly receptive to the simple message of the ultraconservatives. The Salafis promise to find solutions in Islam to all of the many pressing political and socio-economic challenges that young Tunisians face today.
Salafist recruitment methods have become more elaborate. At first they focused mainly on preaching and on organising protests and mass rallies; a gathering last May in Kairouan attracted perhaps 5,000 people.
But they are increasingly providing social welfare services, to win public support and gain members. On Facebook, a Salafi group openly advertises through offering food and clothing to poor young people - a sound strategy in a country where so many people are still struggling to make ends meet.
Despite the increasing visibility of the Salafis, Ennahda's leadership still tries to play down the ultraconservatives' role in post-revolution Tunisia. As Ennahda co-founder Rachid Ghannouchi told me in an interview, "the Salafis are a minority movement; they do not represent Tunisian Islam".
But whether Ennahda likes it or not, the Salafis have evidently become an integral part of the Tunisian landscape, offering a sometimes-violent rival interpretation of Islam.
Clearly, the ruling Islamist party is being challenged. Ennahda tries to attract the young mainly through Islamic lectures and events, and via social activities, including sport and weekend trips. But as the ruling party, it is at a disadvantage - it must take most of the blame for Tunisia's economic recession and political stagnation. This naturally benefits its Islamist rivals.
Integrating young people into the Ennahda movement seems to be a particularly challenging task for the ruling party. Most young Islamists have never had the chance to learn about Tunisian Islam. During his time in power, the dictator Zine El Abidine Ben Ali broke with traditional Islamic education.
The relatives of many of Ennahda's young members were in exile or jail in those days. With their fathers in prison, young militants watched Saudi TV, and so became more conservative than Ennahda's current leadership.
Ennahda leaders acknowledge this problem, stating that the priority of their youth programme lies in Islamic education. "Our young members lack an in-depth understanding of Islam, they are not very cultured", a senior Ennahda militant recently told me. "This is why we provide weekly training sessions for them".
Ennahda's young members often feel at odds with the leadership. For example, one young militant recently confided in me that "many members of the youth branch do not like it that Mehrezia Labidi" - Ennahda's female vice president of the Constituent Assembly - "shakes hands with men. They consider this to be un-Islamic".
He also told me that some young Ennahda militants say they want separate classrooms for men and women, an explicit form of gender segregation that the party's leadership has declined to promote.
Many members of the youth branch were particularly disappointed when Ennahda decided recently to hold talks with Nidaa Tounes, an opposition party that includes politicians who had worked under the former regime.
"Ennahda is negotiating with people who tortured our fathers", said one young member of the ruling party. "Many of the youth branch find this unacceptable."
Owing to this gap between Ennahda's leadership and its youth branch, some young militants have already left the party, a movement accelerated after the party declined to support a reference to Sharia in the constitution.
Until now, Ennahda has lost only a minority of its youth members to the Salafis. But integrating young people into the movement is likely to become increasingly challenging as the ruling party has to take more unpopular political and economic decisions.
This is all the more important in view of the forthcoming constitution, drafting of which is now in its final stages. The document contains many clauses, on women's rights for example, that hardliners consider un-Islamic.
Monitoring the battle between Salafis and the Ennahda movement, then, has become more central than watching the polarisation between secularists and Islamists for anyone who wants to develop an understanding of the path Tunisia's transition will eventually take.
Whether or not Ennahda manages to integrate young people into its movement might determine whether the Tunisian revolution will succeed.
Anne Wolf is a journalist, researcher and political risk analyst based in Tunis