Burma's National League for Democracy, led by democracy campaigner Aung San Suu Kyi, has won an absolute majority in the country's parliament, the election commission has said.
Suu Kyi, who is banned by law from the country's presidency, has said she would take a position "above" the president should her party win a majority.
Thousands of supporters of Burmese political icon have turned out in the streets after the country's freest election in 25 years.
Excited crowds gathered outside the headquarters of Ms Suu Kyi's National League for Democracy (NLD) as the first results of the ballot were read out.
A clear picture of the result is unlikely to be established until Tuesday morning, but the NLD is expected to win the largest share of the vote.
Laws passed previously block Ms Suu Kyi from becoming president, though she has indicated she will stand in a role "above president" should her party win a majority.
The US described the election as "far from perfect", with the military, which has held power since 2011, is guaranteed at least a quarter of the vote
Aung San Suu Kyi's opposition party is on course for a landslide victory in Burma's most democratic election for decades.
The party of Nobel peace laureate Aung San Suu Kyi is expected to prove popular, but may still face an uphill struggle in parliament.
Aung San Suu Kyi always chooses words carefully and as she uttered one sentence it emphatically sounded like a gauntlet being thrown down.