JAKARTA: Indonesian President Susilo Bambang Yudhoyono's bid for re-election was boosted at the weekend when official results showed his party won the most votes in April parliamentary elections.

The final results, released late Saturday, showed Yudhoyono's centrist Democratic Party had won 20.85 percent of ballots cast on April 9, nearly tripling its total from the 7.5 percent it earned in 2004 legislative polls.

"President Yudhoyono was very grateful and expressed his gratitude to Indonesian voters who have given their trust to elect the Democratic Party for the five years ahead," party secretary general Marzuki Ali told AFP.

"We will work very hard for the re-election of President Yudhoyono... hopefully we will get an optimal result." Exit polls found that Yudhoyono has the best chance to win the July 8 presidential election in the world's third-biggest democracy.

The liberal ex-general with an agenda of economic growth and clean government is expected to announce his running mate on May 15.

Golkar, which was former dictator Suharto's political vehicle for three decades, was second in the April polls with 14.45 percent of the vote.

Ex-president Megawati Sukarnoputri's Democratic Party of Struggle (PDI-P) won 14.03 percent, and the Islam-based Prosperous Justice Party (PKS) was in fourth position with 7.9 percent.

Besides the big three, only a handful of the 34 parties that contested the election were able to win more 2.5 percent of votes cast, the minimum threshold for sending representatives to the 560-seat parliament.

Golkar party leader Jusuf Kalla -- Yudhoyono's vice president in the outgoing government -- declared his candidacy for the presidency following a breakdown in coalition talks between their two parties last month.

Kalla -- who is running with ex-military chief Wiranto -- is not thought to have a good chance of winning, but if Megawati also runs, it will create a three-horse race and ensure the polls go to a second round.

Registration at Indonesia's General Election Commission (KPU) for presidential and vice-presidential candidates runs through May 16.