Erik Churchill previews the Sunday vote:
The success of Sunday's election will be judged first and foremost on whether Tunisia will continue with its peaceful transition to democracy. While most observers expect calm, a slight disruption, especially if centered around the fairness of the polls, could quickly degenerate into large disturbances.
Secondly, a strong turnout will show the legitimacy and support of Tunisians for the democratic process. The weakness of the voter registration drive gives cause for concern that Tunisians will not show up on Sunday, potentially delegitimizing the results. Thirdly, Sunday's vote will test whether the government will be able to accept the result of Ennahdha's presumed victory. A result of less than 20 percent could raise calls that the voting was rigged, while an absolute majority by Ennahdha could spark protests from secular groups. This is known as the Algerian scenario, after the Islamist victory of the Islamic Salvation Front in the country's 1991 elections, which sparked a backlash from military regime and ultimately resulted in civil war.