Iran’s June 14 elections will showcase the country’s political system, which, not well understood by many in the West, combines strong Islamic theocracy with elements of democracy. A network of unelected institutions controlled by the powerful supreme leader is countered by a president and parliament elected by the people.

Here's a guide to Iran's labyrinthine governmental operations and a glimpse at some of the men hoping to occupy the top elected office in the country.

According Iran's constitution, the most powerful political office in the Islamic Republic is that of the supreme leader. Since its inception after the 1979 revolution that overthrew the monarchy, two men have occupied the role – the Islamic Republic’s founder, Ayatollah Ruhollah Khomeini, and his successor Ayatollah Ali Khamenei.

The supreme leader appoints the head of the judiciary, six out of 12 members of the powerful Guardian Council, the armed forces’ commanders, the head of the country’s radio and television and Friday prayer leaders, who instruct the faithful in the performance of the Friday prayer in Iran. He also confirms the president's election.

Supreme leader's website via EPA

Iranian Supreme leader Ayatollah Ali Khamenei.

Under the constitution, the president is the second-most-important authority after the supreme leader. The president – currently Mahmoud Ahmadinejad – is elected for a four-year term by popular vote, and can serve no more than two consecutive terms. After a term away he can run for president again.

The president heads the executive branch of government, and is responsible for ensuring the constitution is implemented. 

Powerful clerical councils ultimately answer to the supreme leader.  The supreme leader controls the armed forces and makes most of the decisions regarding security, defense and major foreign policy.

The president appoints and supervises ministers, coordinates government decisions, and selects government policies to be placed before the legislature, but ultimately his power is curtailed by the influential clerical bodies.

All presidential hopefuls have to be vetted by the Guardian Council, the most influential body in Iran. The group, which consists of six theologians appointed by the supreme leader and six jurists nominated by the judiciary and approved by parliament, also has the authority to veto any bill passed by parliament, among other legislative and judicial powers.

An indication of the power held by the clerics and the supreme leader came on Friday when the head of the Guardian Council said it may disqualify presidential candidates who supported full relations with the United States, according to The Associated Press.

The contenders 

Three different tiers of the Iranian establishment appear to be competing against each other in the current elections.  The Guardian Council will release a list of approved candidates – culled from almost 700 who registered – to the Ministry of Interior by May 21.  The following list includes those thought to be most likely to make it onto the shortlist.

EPA, AP file

Candidates for Iran's upcoming presidential election: (from left) Former Foreign Minister Ali-Akbar Velayati; Tehran mayor Mohammad Baqer Qalibaf; speaker of parliament Gholam-Ali Haddad Adel; chief nuclear negotiator Saeed Jalili.

Supreme leader’s favorites
The first camp of contenders consists of the supreme leader’s inner circle and those perceived to be loyal to him.

• Ali-Akbar Velayati, currently the supreme leader’s adviser on international affairs, served as foreign minister under several presidents.  He received a pediatrics degree from Johns Hopkins in 1974. Some observers believe that he lacks charisma when compared with others who are running.
• Mohammad Baqer Qalibaf, Tehran mayor, is a veteran of the Iran -Iraq War. Since he became mayor in 2005, he has embarked on a series of ambitious civic projects that added to his popularity. He may be seen as too independent by conservative clerics.
• Gholam-Ali Haddad Adel, the speaker of parliament, is very much part of the supreme leader’s inner circle – his daughter is married to the supreme leader’s son. But its not clear how much popular support he has.
• Saeed Jalili is Iran’s chief nuclear negotiator. His loyalty to the supreme leader appears unwavering. He also has had substantial dealings with the West, granting occasional interviews and interacting with international counterparts.  

Ahmadinejad’s man
President Ahmadinejad – who has been at odds with the clerical establishment shortly after the disputed elections in 2009 – has put all his political eggs in one controversial basket.  He is backing one figure, the divisive Esfandiar Rahim Mashaei. The two men have been very close for the last 30 years, and Mashaei's daughter married Ahmadinejad's oldest son in 2008.  

Conservative leaders in Iran have gone so far as branding Mashaei the head of deviant current within the government, a heretic and a foreign spy. Despite a chorus of disapproval for powerful members of the establishment Ahmadinejad has stayed loyal to him.

Ebrahim Noroozi / AP

Former Iranian President Akbar Hashemi Rafsanjani waves to media as he registers his candidacy for the upcoming presidential election in Tehran, Iran, on Saturday, May 11.

The ex-president, turned 'outsider'
Ali Akbar Hashemi Rafsanjani – popularly nicknamed ‘The Shark’ because of his inability to grow a beard – is one of the great political survivors of the Islamic Republic.  

Related: Last-minute entry transforms Iranian race

Rafsanjani was the de facto commander-in-chief of the military during the Iran–Iraq War, which raged from 1980 to 1988. He was widely credited with the reconstruction of the country after the devastating conflict.  

Rafsanjani’s involvement with the revolutionary government came early and he became a cleric at the age of 14.  He was elected chairman of the Iranian parliament in 1980 and served until 1989. He is also known as a king maker, and was instrumental in the appointment of Ali Khamenei as supreme leader. 

Slideshow: Everyday life in Iran

At schools, in shops, and on the streets of big cities and small towns, daily life plays out in Iran.

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Rafsanjani served as president of Iran from 1989 to 1997, and 2005 he ran for a third term in office.  He ultimately lost to rival Ahmadinejad in the run-off round.

Rafsanjani advocates a free market economy and is popular with the upper-middle class, who think he may be able to revive the economy.

He fell out of favor with the supreme leader because of his tacit support of the “Green Movement” protest that shook the country and provoked a violent crackdown in 2009. 

Related:

Who's who in Iran's presidential race

Western diplomat on Iran talks: Sides still 'a long way apart'

The leading candidates for Iran's June 14 presidential election, for which registration closed on Saturday.

Akbar Hashemi Rafsanjani: The centrist Rafsanjani, an important figure since the 1979 Islamic Revolution, was president from 1989 to 1997. He earned the ire of hardliners after he sided with reformists during the unrest that followed the disputed 2009 election, and has seen two of his children jailed in recent months. 

Last-minute entry rattles Iranian race

Esfandiar Rahim Mashaie: Former chief-of-staff to outgoing President Mahmoud Ahmadinejad, he is viewed with intense suspicion by conservatives who say he leads a "deviant current" within Iranian politics that seeks to sideline the ruling clerics. They consider Mashaie and Ahmadinejad to be right-wing populists. 

Saeed Jalili: Iran's nuclear negotiator since 2007 is a veteran of the Iran-Iraq war and seen as a hardline conservative close to Supreme Leader Ayatollah Ali Khamenei. 

Hassan Rohani: A moderate Muslim cleric, he also served as Iran's nuclear negotiator, presiding over talks with Britain, France and Germany that saw Tehran agree to suspend uranium enrichment-related activities between 2003 and 2005. He is seen as close to Rafsanjani. 

Ali Akbar Velayati: Served as foreign minister from 1981 to 1997 and advises Khamenei on foreign policy matters. He is seen as a traditional conservative, with ties both to 'principlist' factions - loyal to the supreme leader - and to Rafsanjani's camp. 

Mohammad Baqer Qalibaf: A former police chief, he is the current mayor of Tehran and has a reputation as a competent, charismatic manager who could attract Iran's sizeable youth vote. He is viewed as a pragmatic conservative. 

Gholam-Ali Haddad-Adel: A former parliament speaker and relative of Khamenei by marriage, he is a close adviser to the Supreme Leader. 

Mohsen Rezaie: The veteran politician and former Revolutionary Guards commander ran in 2009 against Ahmadinejad and lost. He is the secretary of Iran's Expediency Council, which advises Khamenei.

The son of former Iranian president Akbar Hashemi Rafsanjani has reportedly returned to Iran from exile to answer charges of inciting unrest after a disputed election in 2009, fueling speculation that Rafsanjani's influence in Tehran may once again be growing. 

Hasan Sarbakhshian / AP file

Former president Akbar Hashemi Rafsanjani, one of the founding figures of the Islamic Republic, incurred the anger of conservatives after backing opposition candidates in 2009 elections.

Mehdi Hashemi Rafsanjani arrived in Tehran late on Sunday, the Iran-based Fars news agency reported, having spent three years in the United Kingdom following his alleged involvement in the widespread protests that followed the re-election of President Mahmoud Ahmadinejad. 

Mehdi Rafsanjani had spent several days in Dubai and had been expected to return to Iran on Sunday, an independent source told Reuters. 

Analysts say his return indicates a deal has been agreed with authorities to resolve the charges he faces, and suggests his father's political fortunes may be reviving. 

Akbar Rafsanjani played a central role in the Non-Aligned Movement summit in Tehran last month, being photographed walking alongside Iran's most powerful authority, Ayatollah Ali Khamenei, and sat next to U.N. Secretary General Ban-Ki Moon. 

If the Rafsanjani family fortunes are changing, it may well have to do with his reputation as a business leader who could help boost the country's flagging economy, NBC News' Tehran bureau chief Ali Arouzi said. 

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As oil sanctions continue to bite and with a presidential election set for next year, some are tipping the pragmatic yet conservative Rafsanjani as a surprise candidate. 

While they have faced persecution in recent years, the family is at the heart of the system and is reputed to be hugely wealthy, Arouzi said.  

"Rafsanjani is a businessman first and foremost," he said. "He could be brought back in to the presidential arena (to) act as a go-between for the hardliners and reformists."

The Rafsanjanis have faced heightened pressure from hardliners since the 2009 vote, which set off the deepest political crisis and worst unrest in Iran since the 1979 Islamic Revolution. 

The former president is one of the founding figures of the Islamic Republic and a close aide to the revolutionary leader Ayatollah Ruhollah Khomeini. 

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But 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. 

Mehdi Rafsanjani's reported return comes 24 hours after another member of the powerful and wealthy Rafsanjani family, his sister Faezeh, began a six-month jail sentence for "spreading anti-state propaganda."

Slideshow: Everyday life in Iran

At schools, in shops, and on the streets of big cities and small towns, daily life plays out in Iran.

Launch slideshow

Her conviction at the start of this year is believed to be over an interview she gave to an opposition news site in which she criticized human rights violations and economic policy in Iran.

NBC News' Ali Arouzi and Reuters contributed to this report. 

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