Updated

Indonesian voters frustrated by persistent corruption and poverty dealt a harsh blow to President Megawati Sukarnoputri (search), with a private poll Monday showing a former general pulling ahead to force a run-off in the country's presidential election.

Susilo Bambang Yudhoyono (search) appeared to ride a wave of public dissatisfaction with Megawati, who was locked in a tight race to even get a spot in the run-off vote against Yudhoyono.

Megawati came to power in 2001 after former President Abdurrahman Wahid was forced out of office by parliament. Voters complain of her perceived aloofness and failure to improve the economy.

"We're suffering," said Mistar, a garbage collector who raises three children on a salary of $3 a day. Like many Indonesians, he uses only one name.

"Yudhoyono seems like a credible man who will listen to us," he said. "I don't think Megawati cares."

A runoff election in September appeared certain, but it was not immediately clear whether Yudhoyono would face Megawati or another ex-general, Wiranto, in the second round, which would take place in September.

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

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.

Yudhoyono failed to win the 50 percent of votes needed for an outright victory in the vote, according to the poll by the Washington-based National Democratic Institute. Official results were not expected for 10 days, partly because of a recount of many invalid ballots.

The democratic institute's poll of votes cast at 2,500 polling stations showed Yudhoyono ahead with 33.9 percent. Sukarnoputri was second with 24.9 percent and Wiranto had 23.8 percent.

The results were based on 63 percent of the total number of votes sampled by the institute, which is the international arm of the U.S. Democratic Party. The poll had a margin of error of 1 percentage point.

Similar polls by the same organization have accurately predicted results in dozens of elections around the world, including Indonesia's parliamentary elections in April.

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, 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 (search).

The election in the world's largest Muslim nation 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.

"This is a wonderful transitional from authoritarian rule to pure democratic rule," said former President Jimmy Carter (search), who was observing the vote in Jakarta.

Yudhoyono said he was confident of getting into the run-off as long as there are no widespread voting irregularities.

As Yudhoyono left the voting booth on Monday, dozens of voters bent and kissed Yudhoyono's hand.

"I have traveled the country and seen the people's support for me," Yudhoyono said.

Megawati 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 by a parliament that accused him of making erratic decisions partly due to his poor health. Megawati, his vice president, replaced him.

In the past five years, her popularity waned because of her failure to combat corruption or improve the economy, and a perception that she is aloof and indifferent to the concerns of the people.

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.