The Five Star Movement was looking for a victory that would have allowed it to run a region of Italy for the first time, and to build credibility as a governing party after lackluster administrations in the major cities where they already hold power, like Rome.

But the movement failed to gain a clear majority in the Sicilian vote. Its avowed refusal to make alliances with other political parties limits the party’s ability to maneuver, even in the event of a strong electoral showing, or to govern.

Furthermore, a new, contested national elections law that passed last month allows parties to run for seats as coalitions, a measure the Five Star Movement says was introduced to keep it out of power.

In any case, no coalition or party managed to win an outright majority in Sicily, forcing negotiations to find other allies, or risk a hung government.

“Berlusconi is a great builder of electoral cartels. He’s always done it, and 20 years after he first entered into politics, he’s still there building these mosaics. But that this is the same as governing effectively is something else, the past shows that it isn’t so,” Stefano Folli, a political analyst for the Rome newspaper La Repubblica, said in a video commentary.

Speaking to supporters Monday evening, Mr. Cancelleri boasted that in Sicily, the Five Star Movement “is the leading political force,” and the electoral results “sent a message to rest of Italy: Finally something can change.” Sicily, he said, represented “the change we hoped for and wanted.”

Mr. Berlusconi, whose party governed Sicily as part of a coalition from 1996 to 2012, also thanked Sicilian voters for choosing “the path for change.” In a video message on his Facebook page, he said that having faced a crossroads, between “our positive revolution, or the inconclusive anger of the Five Stars,” Sicily had chosen “a liberal revolution.”