Burma held a landmark election on Sunday, Nov. 8. Even though Nobel laureate Aung San Suu Kyi’s political party is one of the most popular in the country, she won’t become president. Here’s why. (Jason Aldag and Andrew Katz/The Washington Post)

Aung San Suu Kyi’s political allies on Monday predicted an overwhelming victory in Burma’s elections — a landslide win based on strong early results that prompted their ­military-backed opponents to begin to speak glumly of defeat.

That would be a triumph for Suu Kyi, who has been revered at home and worldwide since she emerged as an advocate for democracy in 1988 and suffered years under house arrest. But weeks of uncertainty could follow as she tries to form a government and find a way around a constitutional provision that bars her from becoming president.

Twenty-five years ago, she and her allies won an election here, but those results were ignored by the military officers running the country. For the past five years, Burma has been taking fitful steps toward democracy, encouraged by the United States and other countries. Experts see the elections held Sunday as a test of whether the generals will truly loosen their grip on power.

The NLD won 49 out of the 54 seats for the lower house of parliament for which the election commission had final results. For the second night in a row, party supporters gathered Monday in front of the NLD headquarters here, clapping, singing, chanting and waving red balloons to celebrate vote totals.

Win Htein, a member of the NLD’s central executive committee, said Tuesday morning that according to its analysis, the NLD has won 82 percent of the nationwide vote, but “we are still counting the seats.” He added that the government election commission “is not being straightforward and is delaying the results.”

Aung San Suu Kyi, the Burmese opposition politician, arrives at the polling station to vote Nov. 8. (Lam Yik Fei/Getty)

The party would have to get 67 percent of the total seats for an absolute majority and the chance to select the next president without having to form an alliance with any of the 90-plus smaller parties. Burma’s constitution, drawn up by its military rulers in 2008, reserves 25 percent of seats in the upper and lower houses of the parliament for the military.

More than a dozen prominent leaders of the ruling Union Solidarity and Development Party, which is backed by the military, were defeated at the polls. Htay Oo, its acting chairman, told the Reuters news agency simply, “We lost.” T-shirts quickly appeared in front of NLD headquarters that said “We won.”

Some USDP members said they had not done enough to ensure victory.

“We are not doing very well. The NLD is in a superior position,” said Soe Min, a USDP member who ran against Suu Kyi in a 2012 parliamentary by-election and lost. “But the votes are still counting.”

The celebration by NLD supporters came a day after millions in Burma voted peacefully in the country’s first democratic elections since 1990. The nation of 51 million, also known as Myanmar, has long been isolated from the world under its repressive military dictatorship.

Appearing before cheering supporters Monday morning at NLD headquarters, Suu Kyi, 70, said it was too early to congratulate winners but added, “I think you all have an idea of the results.”

“Victory or failure, that is not important,” she said. “What is important is how we win or lose. Those who lose should bravely concede, while those who win should humbly celebrate the victory. That is a true democracy.”

Millions of the country’s 30 million eligible voters had braved a hot sun and long lines to cast their ballots on Sunday, and more than 10,000 election observers were on hand. Concerns rose Monday over claims that a number of military ballots had flowed in late Sunday, apparently tipping the balance to the USDP in races in far-flung states. “People stood hours in line in the sun and celebrated yesterday, and today there is a huge disappointment because their vote didn’t count,” said Meenakshi Ganguly of Human Rights Watch, who observed voting in Kachin state.

Suu Kyi’s fate is still unclear, but she said at a news conference last week that she would govern the country despite the constitutional barrier. “I’m going to be above the president,” she said. The remark worried some analysts and activists, who pointed out that such a position — unheard of until now — would violate the constitution.

“She went so far as to say she’ll be ‘above the president,’ ” said Khin Zaw Win, an activist and former political prisoner. “That is not a responsible thing to say. It will worry the other side and reeks of Oriental despotism — the power behind the throne.”

A victory for the pro-democracy party would be a tremendous boost to the Obama administration’s hopes that Burma will become a functioning democracy.

When the military junta began reforms in 2010, Suu Kyi was released from house arrest, other political prisoners were freed, and censorship and restrictions on Inter­net access were relaxed. The United States responded enthusiastically by easing stiff sanctions and providing nearly $500 million in aid. Hillary Rodham Clinton visited once while she was secretary of state, and President Obama has come twice.

But over time, the government of President Thein Sein again began to imprison journalists and critics. Key economic reforms have stalled. The government — in concert with a group of hard-line Buddhist monks — passed laws restricting religious freedom that some say target Muslims. More than 100,000 Rohingya Muslims reside in displacement camps where they have been since sectarian clashes with their Buddhist neighbors in 2012, with scant access to food, health care and education.

Asked at a briefing Monday in Washington about Suu Kyi’s future role, White House press secretary Josh Earnest said the 1991 Nobel Peace Prize winner has been a “powerful voice” for needed reform and change in Burma.

“But ultimately, what set of official responsibilities she will have will be the responsibility of the Burmese people and the Burmese government to determine,” Earnest said.

Secretary of State John F. Kerry said in a statement Sunday that although the elections were an “important step forward,” they were “far from perfect.” He cited the exclusion of the Rohingyas and the reservation of a quarter of parliamentary seats for the military as “important structural and systematic impediments to the realization of full democratic and civilian government.”

Monday night, as the music blared and pro-democracy forces danced and cheered in Rangoon’s streets, one NLD volunteer was more circumspect. Yin Myint May, 60, a doctor, said she was elated but still feared the military. She remembers when armed military officers showed up at her family’s door and tried to arrest her sister, who had given speeches criticizing the government. She fears that the generals will not honor the election results, as in 1990, when they refused to recognize the NLD’s first big victory win at the polls.

“We have to be cautious about it. It’s almost hard to believe,” she said. “So many times they do what they say, and then one or two days later they change their minds.”

Greg Jaffe in Washington contributed to this report.

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