Adianto P. Simamora, Jakarta – The Golkar Party will ultimately "tie the knot" with the Democratic Party in backing President Susilo Bambang Yudhoyono and Vice President Jusuf Kalla in the presidential race, despite mounting calls within Golkar for an end to the coalition, experts say.

University of Indonesia political observer Ali Fachry expressed doubt over a possible Golkar move to form its own coalition to take on Yudhoyono. "[Yudhoyono and Kalla] are complementary. Each becomes fragile if they part ways," Fachry, a close acquaintance of Kalla's, told The Jakarta Post on Sunday.

He said calls for a new coalition with the Indonesian Democratic Party of Struggle (PDI-P) or the Prosperous Justice Party (PKS) were just "emotional statements" from individuals within Golkar.

"Coalitions with other parties are tentative plans, or the very last resort if Yudhoyono picks another running mate over Kalla," said Fachry, author of the book Kalla and Aceh Peace.

Asked whether Kalla stood a good chance of winning the presidency, Fachry said "No. In my personal view, Kalla doesn't have a strong chance in the presidential election if he breaks away from Yudhoyono."

Senior Golkar executive Priyo Budi Santoso said last week a coalition with the PDI-P or the PKS was possible. He added Golkar would name Kalla as its presidential hopeful, while picking a vice presidential candidate from another party.

Paramadina University political scientist Bima Arya Sugiarto said Kalla would require a powerful coalition to face off against Yudhoyono and his Democratic Party, whose popularity is on the rise.

"Yudhoyono is now at his peak. Only a very solid political machinery can defeat him in the election, and Golkar could take the lead," he said. "But the coalition should also seek a candidate other than Kalla to face Yudhoyono," he added, citing Kalla's low popularity ratings.

Bima also said the Democratic Party could abandon Kalla if the party won 20 percent of votes in the legislative elections.

Alfan Alfian from the Akbar Tandjung Institute said calls for Golkar to break from the Yudhoyono-led coalition reflected internal party strife.

"Golkar is in a dilemma over its reluctance to name Kalla as its presidential candidate. Nominating Kalla for the presidential post will also be detrimental for the party because he is far less popular than other candidates," he said.