A former army general with a reputation for honesty won the most votes in Indonesia's first direct presidential election but he failed to get a majority and will face incumbent Megawati Sukarnoputri (search) in a runoff, poll results showed Tuesday.

Susilo Bambang Yudhoyono (search) rode a wave of frustration over corruption and poverty in the world's most populous Muslim nation to lead Monday's voting, but received less than 50 percent support, meaning a runoff between the two top vote-getters will be held Sept. 20.

"We thank God and the people for this," Yudhoyono's campaign manager, Rahmat Witoelar, said of his candidate's first-place finish. "We will enter the second round with a vow to do better."

A private poll by the Washington-based National Democratic Institute on Tuesday showed Yudhoyono with 33 percent, Megawati with 26 percent and Wiranto (search), a former military chief, with 23 percent. The figures were released on Metro TV, a privately owned news station.

The system predicts election results by counting about half a million votes from 2,500 selected voting stations. It has a margin of error of 1.1 percent. Using the same system, the institute has accurately predicted the results of dozens of other elections around the world.

Final official results from Monday's election were not expected for 10 days. By Tuesday, the national election commission had counted over 17 million of 155 million ballots.

According to its figures, Yudhoyono led with 33 percent; Megawati was second with 26 percent, and Wiranto had 23 percent. Amien Rais (search), former head of Muhammadiyah, Indonesia's second-largest Islamic organization, had 14 percent. Hamzah Haz, who has served as Megawati's vice president, had 3 percent.

Vote counters across the archipelago Tuesday were re-examining all ballots initially deemed invalid because voters punched two holes, not one, in them.

It was unclear whether the mixup would affect overall results; elections officials have suggested it would not likely affect them. The campaigns of Megawati and Wiranto said they would accept the final count.

The 54-year-old Yudhoyono has promised answers for Indonesia's endemic poverty, corruption, separatist wars and religious frictions — but he has offered few details.

His military background includes work in East Timor (search), the Portuguese colony Indonesia invaded in 1975, and there are questions about his alleged role in human rights abuses.

He served as Megawati's security minister after leaving the army and tried to bring peace to the restive province of Aceh last year. That effort collapsed after Megawati sided with hard-line army generals demanding an offensive.

If Yudhoyono wins, analysts predict he will maintain the present policy supporting the U.S.-led campaign against Al Qaeda.

Yudhoyono has seen his support rocket amid perceptions that he is clean, honest and tough.

Analyst Salim Said said the second round would be a "wild affair" because intense horsetrading and coalition building was likely to begin in the run-up to the September vote.

Indonesia's currency strengthened and shares opened 1.7 percent higher Tuesday following the peaceful election. But the outlook remains cloudy because of the possibility of further political uncertainty ahead of September's run-off vote, market analyst Rizal Prasetijo said.

Monday's vote took place six years after the ouster of longtime dictator Suharto, and was seen a key step in the transition to democracy in the world's largest Muslim country.

She emerged as a popular politician in the tumultuous days following the 1998 ouster of Suharto, who had ruled Indonesia since overthrowing Megawati's father, Sukarno, in 1966. Her party won more than a third of the vote in free elections in 1999.

In 2001, Wahid was forced from office and replaced by Megawati, his vice president. But in the past three years, her popularity waned because of her failure to combat corruption or improve the economy.

The other possible candidate in a run-off, Wiranto, is a former commander of the armed forces who has been indicted by U.N. prosecutors in East Timor for crimes against humanity allegedly committed in that former Indonesian province in 1999.

The election was a massive enterprise, with more than 155 million eligible voters spread across 13,000 islands and three time zones. Previously, presidents were selected by lawmakers acting as an electoral college.