Iran presidential candidates
Jalili is a hardliner backed by many in Iran's ruling theocracy including the supreme leader, Ayatollah Ali Khamenei.
He has been Iran's top nuclear negoiator since 2007.
At campaign stops, Jalili's slogan was chanted by supporters: "No compromise; no submission." Jalili also is often hailed as a "living martyr" because of losing part of his right leg in 1980-88 war with Iraq.
Hassan Rowhani
Rowhani is a former nuclear negotiator and close ally of former President Akbar Hashemi Rafsanjani, who was blocked from the ballot by Iran's election overseers.
Rowhani, 64, is the only cleric among the candidates and viewed as a relative moderate. He has drawn support from reformist leaders after a rival, former Vice President Mohammad Reza Aref, dropped out of the race in an attempt to consolidate the liberal-leaning camp.
Baqer Qalibaf
He is the mayor of Tehran and a former commander of the Revolutionary Guard during the Iran-Iraq war.
Qalibaf, 51, has built a reputation as a dynamic leader for a host of quality-of-life projects around Iran's capital including parks, expanded subways lines and highways. But he also has faced accusations that he took part in crackdowns against student protesters in 1999 while with the Guard and, four years later, allegedly ordered a full-scale assault to crush another flare-up of student unrest.
Ali Akbar Velayati
Velayati, 67, served as foreign minister during the 1980-88 war with Iraq and into the 1990s. He was among the suspects named by Argentina in a 1994 bombing of a Jewish center in Buenos Aires that killed 85 people.
Velayati was proposed by Khamenei - who was then president - to become the first prime minister. He was rejected by parliament and the post went to Mir Hossein Mousavi, who led the reform-minded Green Movement in the president election in 2009.
Velayati hinted during a pre-election debate that he might attempt to temper Iran's intransiegence in nuclear negotiations with the West should he be elected, giving an unusually public glimpse into the split between some of the conservative candidates on the topic.
Mohsen Rezaei
Rezaei, 58, ran in 2009, but finished fourth. He currently is secretary of the Expediency Council, which mediates between the parliament and Guardian Council. Rezaei is also charged by Argentina for the Buenos Aires bombing.
Rezaei was a key member of an underground Islamic guerrilla group fighting the U.S.-backed shah in the 1970s and protecting leaders such as Ayatollah Ruhollah Khomeini. After the 1979 Islamic Revolution, Rezaei became chief commander of the Revolutionary Guard near the beginning of the 1980-88 war with Saddam Hussein's Iraq, which was then backed by Washington.
Mohammed Gharazi
A former oil and telecommunications minister, Gharazi, 71, also served in parliament in the 1980s and '90s. He is considered conservative and portrays himself as a steady-handed technocrat.
Gharazi was part of the anti-shah faction forced into exile before the Islamic Revolution. He then joined parliament and was later appointed to the influential position of oil minister. He later served on the Tehran city council. His campaign has focused on reviving Iran's sanctions-wracked economy.