Azerbaijan's governing party staged a rally Thursday to celebrate its victory in parliamentary elections, but a growing alliance of opposition parties said the vote should be overturned and rescheduled.

Thousands of pro-government demonstrators held up Azerbaijani flags and chanted "Ilham," referring to President Ilham Aliyev, whose New Azerbaijan Party swept elections that the United States and European governments said were riddled with fraud. U.S. and European leaders had hoped that the vote last Sunday in the energy-rich former Soviet republic would mark a step toward democracy, as Aliyev had promised.

Instead, there were often crude displays of ballot-stuffing, voter intimidation and the rewriting or abandonment of unfavorable counts, diplomats and election observers said. The government has admitted to small violations, none of which would affect its control of parliament.

"They are approaching the limits of Western patience," said Norway's ambassador to Azerbaijan, Steiner Gil, whose country is a major investor here. "This is disgusting. It's absolutely unacceptable."

Opposition leaders, who have a history of fractious rivalry, said Thursday they had united under a single banner, the Democratic Front, in their attempt to press for new elections. Aliyev's party won 62 seats in the 125-seat parliament, while the opposition won 10. The balance was taken by smaller parties and independents, many of whom are loyal to Aliyev.

"Our struggle is not for seats in the parliament," said opposition leader Isa Gambar after a meeting of opposition party leaders. "We want the election to be canceled and a new vote to be held."

Parade marshals, many of them government workers wearing cream-colored jackets, funneled the crowd into columns, which then marched into a square where the opposition had also assembled the day before.

"The victory of our party is victory for our president. Hail our president," said Ali Akhmedov, a governing party leader. But even as he was speaking, a stream of people began to leave.

Up to 20,000 people attended the rally, but it was hard to determine how many came willingly.

Students, led by their teachers, were among the participants, and when their chaperons weren't looking, many indicated they did not want to be there. Foreign diplomats said they had received reports that students and workers were told they had to attend.

"People were forced to come from all the offices," said one woman, who like most people interviewed declined to give her name.

State television broadcast images of the rally, with cameras on mechanical arms sweeping over the crowd. There were no images broadcast of the opposition rally, and it was mentioned only briefly on the evening news.

The opposition said it would hold another rally Saturday, and that demonstrations would be expanded to other parts of the country.