JAKARTA (Reuters) - After winning Indonesia's closest ever presidential election, Joko "Jokowi" Widodo now faces what could be his toughest battle yet - winning over his own party.
To do that, he must deal with Puan Maharani, the politically ambitious daughter of former president Megawati Sukarnoputri and a powerful figure in the Indonesian Democratic Party-Struggle (PDI-P) that her mother heads and which propelled Jokowi into the presidential palace.
For some, there is a risk of a power struggle among the rank-and-file of Indonesia's most popular party that could muddle Jokowi's agenda in parliament, where Puan is party leader.
"The leadership of PDI-P is still not united in their support," one party insider, who like most party officials, declined to be identified because of the sensitivity of the matter, said of Jokowi's backing.
"Puan does have followers ... of course, they are threatened by somebody like Jokowi."
Puan is heir to a political dynasty that goes back to her grandfather and founding president, Sukarno.
Jokowi is the new face of national politics, seen by some as an upstart who threatens the grip of the established political elite.
While the party puts on a united front in public, behind the scenes suspicion simmers, party insiders say.
Many of the party's old guard reluctantly backed Jokowi as their presidential candidate only after Megawati, well aware her chances of running successfully for the presidency this time were next to zero, put her own ambitions aside and offered the nomination to the hugely popular Jakarta governor.
But the can-do governor who has become Indonesia's most popular politician nearly did not make it.
After leading by as much as 30 percentage points in opinion polls a few months before the presidential election, infighting and indecisiveness within his party saw the lead shrink to just five points.
The party was also seen as having squandered chances of pulling in more votes in April's parliamentary election, though it still came out on top.
After the April vote, Jokowi went public with his disappointment with the results and how the campaign was run. Media saw that as an unmistakeable sign of tension between the presidential candidate and Puan, who ran the campaign.
But Jokowi, in an interview with Reuters, denied there was any conflict with Puan: "In our party there are a lot of political dynamics. I think that's normal."
Other top PDI-P officials did not respond to requests for comment.
Despite his denial of a rift, Jokowi is likely to be looking over his shoulder at his own ranks as he prepares to start his five-year term in October, almost as much as he looks to square off with the opposition.
"Jokowi needs to make sure he won't be challenged by his own party in the parliament to pursue his budget and his policy proposals," said Phillips Vermonte, political analyst at Jakarta-based think-tank CSIS.
"He needs to make sure the party is in his full control."
Like Rahul Gandhi of India's Congress Party, Puan is seen by many as PDI-P's heir apparent.
"She believes that the party belongs to the family and she is the heir. There is a sense of entitlement," the PDI-P insider said.
Puan, 40, was elected to parliament in 2009 and was heavily involved in her mother's failed presidential campaign that year. She is the PDI-P's deputy of politics and was in charge of this year's legislative campaign.
The Puan faction believe Jokowi, 53, has climbed up the political ladder too quickly, butting in front of long-time party loyalists in an unprecedented rise from small-town mayor to Jakarta governor to the leader of the world's third largest democracy in less than a decade.
They fear Jokowi's team and all of his supporters will push them out, overhaul the entire party, and leave Sukarno's direct descendants out in the cold.
"They ... feel that their positions can be protected by Puan because they feel that Megawati is too aloof," the PDI-P insider said. "That's where (Puan) gets her power and confidence."
When Megawati turned to Jokowi as the party's presidential candidate, Puan supporters pressed for the daughter to be his running mate. But the role went to a former vice president, Jusuf Kalla.
In an interview with Reuters, Kalla said Puan needs to build up her political experience over the next five years as a minister or as the speaker of parliament. Then she could be in a good position to replace him as Jokowi's running mate in 2019.
Despite the tensions within the party, PDI-P officials say that once a decision is made by Megawati the discussion ends - reflecting the power of the party boss.
"Don't paint it as though there's friction within the party," PDI-P lawmaker Rieke Diah Pitaloka told Reuters.
"Arguments are not unusual, especially within the PDI-P. We can have heated arguments, but when an instruction comes out, we follow."
The PDI-P is expected to hold its next national convention in May 2015 and Puan is expected to try for party boss if her mother steps down.
Jokowi told Reuters in an interview last week that he would not go for the top PDI-P job.
"This is good for my country because I'm not head of the party ... government is government, party is party," he said.
(Additional reporting by Jonathan Thatcher and Gayatri Suroyo; Editing by Robert Birsel)