Jakarta governor and presidential contender Joko Widodo says the question of his running mate will be decided by his Indonesian Democratic Party-Struggle (PDI-P) and its chairman, former president Megawati Sukarnoputri.
That decision is unlikely to come before the April 9 general election, and Mr Joko, 52, did not give an indication of timing in his first interview after being named the party's candidate for the top job.
But he told Kompas TV his own nomination was the result of a "long process".
"We hope PDI-P will win with a high percentage in the legislative election so there's a strong government, backed by strong assemblies and Parliament," he added.
Mr Joko's entry into the presidential race has, overnight, radically changed the dynamics as full-scale campaigning for the general election started on Sunday.
PDI-P is expected to gain a significant jump in its vote share, as projected by several recent surveys, were Mr Joko to be named its candidate before polling day.
These polls found the party would get below 20 per cent of the votes on April 9 if it did not name Mr Joko as its candidate, and at least 27 per cent if it did, well ahead of closest competitor Golkar.
An Indo Barometer poll in January found that the party could get 35.8 per cent, surpassing the 33.7 per cent popular vote it got in 1999.
Political analyst Hanta Yuda told a forum on Saturday: "Almost all parties are not happy with Jokowi's nomination. If the PDI-P gains votes, all other parties will see their share decline."
Particularly hit will be smaller parties, which may find it hard to meet the 3.5 per cent threshold of popular votes nationwide needed to enter Parliament.
The presidential election takes place only three months later, on July 9.
Given Mr Joko's commanding lead in public opinion polls, a major focus will be the intense jostling to be his running mate.
Already, veteran politician and former vice-president Jusuf Kalla's name has surfaced as a favourite for the No. 2 post.
An Indo Barometer poll released last Wednesday found that a Joko-Kalla pairing would get 36 per cent of votes in July.
Yesterday, Mr Kalla, 71, reminded Mr Joko and his party to consider carefully the matter of a running mate.
Drawing a comparison with the two leaders who declared Indonesia's independence in 1945, he said: "We have to look to experience. Sukarno and (Mohammad) Hatta complemented one another. That's the formula: Each complementing the other."
Mr Kalla, a businessman and former Golkar chairman, also heads the Indonesian Red Cross and the council of mosques.
Some see their combination mirroring that of United States President Barack Obama and veteran senator Joe Biden, both of whom are now the same age as Mr Joko and Mr Kalla.
However, a group of 22 retired senior generals led by former trade minister Luhut Panjaitan say the ideal presidential combination should include a former military man. Names that have surfaced include former army chief Ryamizard Ryacudu and current armed forces commander Moeldoko.
They are expected to put up a fight against Mr Joko's likely key rival, former general Prabowo Subianto of the Gerindra Party, who many surveys tipped to win the presidential poll if Mr Joko did not stand.
Yesterday, Gerindra chairman Suhardi told reporters Mr Joko's candidacy did not bother the party, as Mr Prabowo had won the people's hearts, and people were looking for a leader who could solve the country's problems.
Democratic Party executive chairman Syarief Hasan said Mr Joko was not a threat to his party, and his naming was good for the nation.
But Golkar party strategist Indra Piliang was more blunt, saying his chairman and presidential pick Aburizal Bakrie would have to name a running mate fast to gain an edge.
Mr Indra also took a dig at Mr Joko's lack of national experience: "Does he know all the problems in Indonesia, from Aceh to Papua?" Similar questions are set to be a downside factor for Mr Joko, who will now come under greater scrutiny, with rivals and critics ready to pounce on any small misstep.
Already, pockets of PDI-P members who wanted Ms Megawati to stand again are saying they will sit out the election.
Mr Hanta says Mr Joko has to clearly spell out his vision for the country if he were to be president.
Gadjah Mada University political scientist Ari Dwipayana says that either way, Mr Joko's naming is likely to make the competition tighter and see voter turnout rise beyond the 71 per cent in 2009.
"The number of undecided voters is likely to drop, and turnout could be as high as 80 per cent," he told The Sunday Times.
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