JAKARTA - Indonesia's presidential election campaign period officially opened Tuesday with opinion polls showing incumbent Susilo Bambang Yudhoyono holding a huge lead over his rivals ahead of the July 8 vote.

The liberal ex-general is riding high after his centrist Democratic Party tripled its vote in April's general elections, snaring more than 20 per cent of the ballots compared to around 14 per cent for the main opposition.

"We are confident that the presidential elections will be carried out in a fair, smooth and peaceful manner," Election Commission spokesman Syafriadi Yatim said.

Yudhoyono, known in Indonesia by his initials, SBY, won a landslide victory over Democratic Party of Struggle leader and ex-president Megawati Sukarnoputri to become the country's first directly elected head of state in 2004.

He is hoping for a second term to make good on his promises to clean up rampant corruption and steer Southeast Asia's biggest economy out of the global recession.

Sharing a ticket with respected economist and former central bank chief Boediono, the mild-mannered Yudhoyono will be hoping to win more than 50 per cent of the vote to avoid a second round in September.

"We are confident of getting 55 to 70 per cent of votes, based on recent polls," Yudhoyono campaign adviser Darwin Zahedy Saleh told AFP.

"The SBY-Boediono pair is consistent in their vision to promote democracy, uphold laws that fight corruption, reform the bureaucracy and come up with economic programmes that will grow the economy with quality and equity."

But Yudhoyono's plans for a first-round win over Megawati received a blow when his previous running mate, outgoing Vice President Jusuf Kalla, announced he would make his own bid for the presidency as head of the Golkar Party.

Kalla is a distant third in the opinion polls but his entry makes it a three-horse race and a first-round result less likely.

During months of public negotiations over power-sharing deals, Megawati and Kalla both chose former generals with chequered pasts as their running mates.

The presence of ex-military men in all three leading campaigns is evidence, analysts say, that old elites remain powerful in Indonesia 10 years after the fall of Suharto's military-led government.

Megawati has teamed up with notorious special forces ex-commander Prabowo Subianto, who is accused of serious human rights violations, including the kidnapping of activists on behalf of the Suharto government in the 1990s.

Kalla has chosen former military chief Wiranto, who has been indicted by the United Nations for crimes against humanity including murder, deportation and persecution over East Timor's bloody independence referendum in 1999.

Aria Bima, an adviser to Megawati, said the daughter of national independence hero Sukarno could win 30 per cent of the vote despite her reputation for inaction and the corruption of her 2001-2004 administration.

"Under SBY, the economic situation was not much better and many people are disappointed in him. I'm sure we can get these people to support us," he said.

Growth is expected to fall from above six per cent last year to around four per cent in 2009, but the economy should avoid recession thanks to strong domestic demand, analysts say.

A poll published last month by the Indonesian Survey Institute found that 70 per cent of 2,014 respondents would vote for Yudhoyono, compared with 21 per cent for Megawati and a mere three per cent for Kalla. -AFP