PHNOM PENH, Cambodia -- Thousands of supporters of Cambodia's opposition rallied against the authoritarian government of Prime Minister Hun Sen on Saturday, calling for the United Nations to help lead an investigation into accusations of cheating in the July 28 national elections that the governing party says it won.
Protests by farmers and strikes by garment workers are relatively common in Cambodia, but Saturday's demonstration by a newly unified political opposition was one of the most potent symbols of defiance against Mr. Hun Sen in recent years.
The leaders of the opposition, Sam Rainsy and Kem Sokha, told demonstrators that they would stage additional protests until their demands were met.
"We want a leader who is full of dignity, not a leader who steals votes," Mr. Kem Sokha, the vice president of the opposition Cambodia National Rescue Party, told the crowd on Saturday. "We will not stop until there is a solution."
Analysts question how long opposition supporters will remain passionate about the issue. The three-hour protest, which was peaceful and largely confined to a public square, seemed relatively unthreatening to the 28-year-long rule of Mr. Hun Sen, who in addition to the apparent loyalty of the army and the police has a praetorian guard of thousands of soldiers. His party machinery is firmly entrenched throughout the country, its domination stretching from national institutions to village patronage networks.
But the usually demonstrative and garrulous prime minister has been relatively quiet in recent weeks, leaving analysts guessing about his next moves. The opposition says it will not attend National Assembly sessions until the election irregularities are addressed, but some members of Mr. Hun Sen's party say they plan to form a new government with or without the opposition's attendance.
Despite demands by the opposition to withhold official election results until the political standoff is resolved, Mr. Hun Sen's party, the Cambodian People's Party, is expected to be declared the victor by the National Election Committee on Sunday. Analysts say the official results are not likely to differ significantly from preliminary tallies by the committee, which showed the Cambodian People's Party winning 3.2 million votes compared with 2.9 million for the opposition, an uncomfortably slim margin for Mr. Hun Sen, who has dominated the country's politics for decades.
Cambodian and international election monitors have pointed to numerous, significant irregularities in the elections that have the potential to alter the outcome.
"We can't say with confidence that these elections reflected the will of the people," said Laura Thornton, the resident director of the Cambodia office of the National Democratic Institute for International Affairs, an American organization that promotes elections.
Among the biggest issues was the large number of temporary identification cards the government issued before the election. Although temporary cards are normally reserved for those who lose their ID cards, the National Election Committee has said that as many as 800,000 temporary cards were issued, or about 1 per 12 eligible voters.
Ms. Thornton said the government, despite repeated requests, had not explained why so many people needed temporary identification cards to vote. Initial data collected by her organization shows that the use of temporary cards was concentrated in areas where the governing party was in a close contest with the opposition, raising the possibility that the ID cards could have been used illegally as a tool to allow ineligible voters like minors or foreigners to vote.
On Friday, the Constitutional Council, a body that according to Cambodian law has the final say in election complaints, rejected the opposition's claims of irregularities.
This article originally appeared in The New York Times.