Former President Hashemi Rafsanjani was picked Tuesday as head of a powerful clerical body charged with choosing or dismissing Iran's supreme leader, state-run television reported. Rafsanjani received 41 votes to become head of the Assembly of Experts, a body of 86 senior clerics empowered with monitoring Iran's supreme leader, currently Ayatollah Ali Khamenei, and choosing his successor. The powerful former president, who is considered more moderate than current hard-line President Mahmoud Ahmadinejad, defeated Ayatollah Ahmad Jannati, an extremist within the hard-line camp who received 34 votes, state TV said. Rafsanjani succeeded Ayatollah Ali Meshkini who died after a long illness in July. The election of Rafsanjani was seen as another defeat to hard-liners and a victory to moderate conservatives within Iran's ruling Islamic establishment. It could also mean a challenge to Khamenei, who as supreme leader has final say on matters of state. While extremists such as Jannati are among the proponents of the theory that the legitimacy of Iran's clerics to rule the country is derived from God, Rafsanjani, who is considered an opponent to Ahmadinejad and lost to him the 2005 presidential runoff, is believed to side with pro-democracy reformers who believe the government's authority is derived from popular elections. The Experts Assembly is considered the pillar of the regime because of its lofty duties: monitoring the all-powerful supreme leader and picking a successor after his death. But the Assembly has not published a single public report about its monitoring of Iran's supreme leader in the past three decades. On Tuesday, Rafsanjani said perhaps the Assembly's "decisions will be made public someday," according to the official news agency, IRNA. "If the Experts Assembly wants to play a more active role in the country's affairs, it has the religious and legal justification to do that. ... Perhaps the assembly will do so in its upcoming term," IRNA quoted Rafsanjani as saying just before the vote Tuesday. The Assembly's real clout kicks in after the supreme leader is gone - a sort of Iranian version of the Vatican's College of Cardinals when they gather to pick a new pope. The assembly has done that only once since the 1979 Islamic Revolution. In 1989, it picked Khamenei to succeed his late mentor, the Islamic Revolution patriarch Ayatollah Ruhollah Khomeini. Analysts said Tuesday's vote showed the moderate conservatives were gaining ground in Iran where there is growing discontent for the ruling hard-liners over rising tensions with the West and a worsening economy. "Rafsanjani's election is yet another no to the fossilized extremists such as Jannati and Mesbah Yazdi. Given differences between Rafsanjani and Khamenei, the election of Rafsanjani is seen as a challenge to the supreme leader," said political analyst Hamid Reza Shokouhi, referring to Ayatollah Mohammad Taqi Mesbah Yazdi, who is Ahmadinejad's spiritual mentor. Prominent analyst Saeed Leilaz said Rafsanjani has spoken lately of greater Assembly supervision over Khamenei. "Recently, Rafsanjani talked about the assembly increasing his monitoring of Khamenei. The outside world must know that Rafsanjani's election today is an important development in Iran," he said. The 73-year-old Rafsanjani - who served as president from 1989-1997 - also heads the powerful Expediency Council _a body arbitrating between legislators and the Guardian Council, a hard-line constitutional watchdog. In December, Rafsanjani won the largest number of votes in his re-election for a seat in the Assembly of Experts. The former president has long been an elusive inside player in Iran's clerical leadership. He has supported a policy of improving relations with the West including the United States. Though he backs the line rejecting a suspension of Iran's uranium enrichment program, he has shown a willingness to compromise in backroom negotiations on the nuclear program. Over the years Khamenei, meanwhile, has increased his power after he was under the shadow of the then-President Rafsanjani when he first was chosen to be supreme leader. In recent years, Khamenei has allowed hard-liners to undermine Rafsanjani's influence, part of his efforts to bring the former president under his control.