There were seven main candidates in the first round of Iran's presidential election.
AKBAR HASHEMI RAFSANJANI
Aged 70, he has been active in politics for over 40 years. Served as parliament speaker (1980-89) and twice as president (1989-97). Currently chairman of the influential Expediency Council which rules on disputes between the Majlis (parliament) and the Guardian Council, the country's main supervisory
A member of the conservative Militant Clergy Association, Mr Rafsanjani is often termed a "pragmatic conservative". As president he gave priority to economic over political development, which critics said hampered social change and led to human rights abuses.
He took over as armed forces commander in 1988, the last year of the war with Iraq, and is seen as instrumental in Iran's acceptance of the UN Resolution which ended the war. His influence in Lebanon helped bring about the release of Western hostages in the early 1990s.
He studied Islamic jurisprudence with the founder of the Islamic Republic, Ayatollah Khomeini. Married with five children. His daughter, Faezeh Hashemi, advocates women's rights and her journal Zan (Woman) was closed down by hardliners in 1997.
A former cabinet minister, Dr Moin is currently adviser to President Khatami. His candidacy is backed by the reformist Participation Front. He served twice as Minister of Culture and Higher Education, under President Rafsanjani (1989-1993) and President Khatami (1997-2003).
During the latter term he submitted his resignation three times, in 1999 in protest at the suppression of student riots, then twice in 2003 over what he called "meddling" by the authorities in his work. On the third occasion his resignation was accepted, "with deep regret", by President Khatami.
Born in 1951 in Najafabad he graduated in paediatrics in 1980 and obtained a PhD in immunology from Tehran University in 1996. Married with two children.
Dr Ali Larijani headed Iran's state broadcaster IRIB for 10 years until 2004. Before that he served as Minister of Culture and Islamic guidance under President Rafsanjani.
The Islamic Co-ordination Council, Iran's main conservative alliance, chose him as its candidate in April. He is currently security adviser to Iran's supreme leader, Ayatollah Ali Khamenei.
Born in 1957, he is the son of late Grand Ayatollah Haj Mirza Hashem Amoli. He graduated in mathematics and computer sciences and has postgraduate degrees in Western philosophy from Tehran University.
Tehran Mayor Mahmoud Ahmadinejad is backed by the conservative political group Abadgaran, or Developers, who dominate the current parliament.
His website says he was a founding member of the student union which took over the US embassy in Tehran in 1979. Since becoming mayor in May 2003 he is known to have quarrelled with reformist President Mohammad Khatami.
Mr Ahmadinejad was born in Garmsar near Tehran in 1956. He studied civil engineering in Tehran and obtained a doctorate in transport in 1997. As mayor, he has tried to solve Tehran's traffic problems.
A veteran politician as well as a cleric, he served as a an MP for 16 years and Majlis speaker for eight. He is identified with the reformist camp and backs consensus politics within the ruling system.
He split from the conservative-controlled Militant Clergy Association and founded the left-leaning Militant Clerics in 1988. He has headed the group ever since.
After the death of Ayatollah Khomeini, to whom he was close, he suffered a setback as the conservatives' power increased. He supported the reformist camp after Mohammad Khatami's rise to power in 1997.
Born in Aligudarz in 1937, he was active against the Shah and arrested several times. Married with four sons.
A vice-president under President Khatami, he chairs Iran's Physical Education Organisation. He describes himself as an "independent reformist".
He worked in industry in the 1980s and early 1990s, and was vice-chairman of Iran's Atomic Energy Organisation from 1993-1995. He is said to be the official who signed a contract with Russia in 1992 to build the Bushehr nuclear power station.
From 1997-2001, he was governor of Khorasan, Iran's largest province at the time. Born in Maragheh in northwestern Iran in 1956, he is a mechanical engineer and is married with three children.
MOHAMMAD BAQER QALIBAF
Dr Mohammad Baqer Qalibaf is a conservative candidate and at 43 the youngest to stand. In July 1999 he was one of the 24 Revolution Guards commanders who sent a letter to President Khatami, urging him to quash the student unrest.
Appointed chief of police in 2000, he set out to modernise the force and recruited women for the first time. He resigned to run in the election.
He joined the Basij paramilitary volunteers in 1980 and fought in the Iran-Iraq war. At the age of 22 he was appointed division commander. He was appointed commander of the air wing of the Revolution Guards in 1997.
Born in the holy city of Mashhad in 1962, he is married with three children. He took a PhD in geopolitics in Tehran in 2001.
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