DUBAI (Reuters) - An adviser to Iran's Supreme Leader Ayatollah Ali Khamenei joined the presidential race on Friday, with powerful conservatives keen to make the June vote a peaceful contrast to the upheaval that followed the disputed 2009 poll.
Khamenei has the final say on all matters in Iran and in theory stands above the political fray, but it is thought he wants a reliable follower in the presidency after Mahmoud Ahmadinejad's two turbulent terms in office.
Reformist groups have been suppressed or sidelined since 2009 and the next president is likely to be picked from among a handful of politicians known for fealty to Khamenei, minimizing the chances of political rifts leading to post-election chaos.
Former parliament speaker Gholam-Ali Haddad-Adel registered to run, state news agency IRNA reported, becoming the first of a trio of Khamenei loyalists expected to do so.
Allied with Haddad-Adel are former Foreign Minister Ali Akbar Velayati and Tehran mayor Mohammad Baqer Qalibaf - Iranian media say two of them will step aside later in favor of whoever appears to have the best chance of winning the election.
"Our final choice will be announced after the Guardian Council's decision," the semi-official Fars news agency quoted Haddad-Adel as saying after registering, referring to a body which vets applicants before they are allowed to run.
The conservative council, normally made up of six clerics and six jurists, will publish the final list of candidates it has approved later this month.
The June 14 vote is a test for Iran after Ahmadinejad's re-election in 2009 ignited the biggest street protests in the Islamic Republic's history, badly denting the legitimacy of its entrenched leaders and its hybrid clerical-electoral system.
But there is little of the popular enthusiasm there was in the run-up to the 2009 election when many sensed there was a possibility of real change in Iran. After years of ever tougher international sanctions over Tehran's nuclear program, many Iranians care more about the economy than political infighting.
The election is unlikely to have much effect on Tehran's nuclear policy which is closely controlled by Khamenei.
The most powerful person in Iran, Khamenei endorsed Ahmadinejad's victory in 2009, rejecting opposition charges of election fraud. But the president later alienated the leader by pursuing his own policies in often provocative ways.
Khamenei is now thought to want to thwart any attempt by Ahmadinejad to preserve his influence by promoting a favored successor, possibly the outgoing president's former chief of staff, Esfandiar Rahim Mashaie.
Conservatives are vehemently opposed to Mashaie who they accuse of promoting a "deviant current" within Islam that undermines the role of the clergy. If he does run, it would be seen as a direct challenge to Khamenei's authority.
Among other candidates who registered on Friday were veteran Iranian politician Mohsen Rezaie, who lost to Ahmadinejad in 2009, and reformist Mohammad Reza Aref, who served as vice-president under former moderate President Mohammad Khatami.
Khatami, who was elected in landslide victories in 1997 and 2001, has not made it clear whether he will run this time but on Friday he threw his support behind moderate former President Akbar Hashemi Rafsanjani and urged him to stand in the vote.
"I believe the best person who can help the establishment and solve the current problems is Mr. Hashemi. I hope he runs in the election," the Iranian Students' News Agency (ISNA) quoted Khatami as saying.
Some analysts say Rafsanjani's candidacy could ignite the contest as he can attract reformist voters.
Rafsanjani, who lost to Ahmadinejad in the 2005 presidential race, is one of the founding figures of the Islamic Republic. He is a veteran politician who wants better ties with the West and would be likely to pursue a pragmatic reform program.
But the former president from 1989 to 1997 has faced heightened pressure from hardliners since the last presidential vote. His backing of opposition candidates in 2009 and sympathy for opposition demonstrators incurred the anger of conservatives and led to a decline in his influence.
Candidate registration started on Tuesday and ends on Saturday.
(Reporting by Zahra Hosseinian; Additional reporting by Yeganeh Torbati; Editing by Alistair Lyon and Jon Hemming)