The Indonesian Survey Circle (LSI) released the results of its June 1-7 poll on Sunday, showing the president’s rating at 47.2 percent, down from 56.7 percent in January.

Sunarto Ciptoharjono, a senior LSI researcher, said the decline was mainly due to the string of graft scandals under his term, especially the case of former Democrat treasurer Muhammad Nazaruddin.

“There are many unresolved cases such as the Bank Century bailout, the murder of rights activist Munir Said Thalib and the corruption cases involving Nazaruddin — a member of Yudhoyono’s party,” Sunarto said.

“This is critical point for the president,” he said. “He should make a move [to boost his popularity] before 2014, or it will affect the Democrats’ chances in the elections.”

He said the perception that the president had been slow to act on these allegations had hurt his credibility. “The allegations of corruption cases involving Democrat officials have destroyed the president’s anticorruption image,” the researcher said.

Nazaruddin was fired from his party post and fled to Singapore before he could be questioned by the Corruption Eradication Commission (KPK) over a graft-tainted construction deal for the Southeast Asian Games.

He has since accused several other high-ranking members of the ruling party of various acts of corruption.

Yudhoyono’s approval rating has declined steadily in a series of surveys published by the LSI since January 2010, when he posted a 60.7 percent rating. This has since dropped to 56.7 percent in January this year.

The president’s rating would have been even lower if the survey had been carried out after the execution of an Indonesian maid in Saudi Arabia, Sunarto noted.