The following are potential front-runners in Iran's June 14 presidential election to succeed Mahmoud Ahmadinejad. The list of candidates will be announced next week after vetting by Iran's ruling clerics:
AKBAR HASHEMI RAFSANJANI: Served as president from 1989-97 and lost a comeback bid to Ahmadinejad in 2005. Rafsanjani is a fierce critic of Ahmadinejad and could become the main candidate for reformists and liberal-leaning voters. He also lost standing among the ruling clerics for publicly criticizing the crackdowns after Ahmadinejad's disputed re-election in 2009. Rafsanjani, 78, is currently head of the Expediency Council, an advisory body that mediates disputes between the parliament and the Guardian Council, the group that vets candidates for the presidency and parliament. He is conservative, but also seen as pragmatic and willing to cut deals with other factions. In the past, he has urged for better ties with the U.S.
ALI AKBAR VELAYATI: Top adviser to Supreme Leader Ayatollah Ali Khamenei on international affairs. Velayati, 67, served as foreign minister during the 1980-88 war with Iraq and into the 1990s. He is a physician and runs a hospital in north Tehran. He was among the suspects named by Argentina in a 1994 bombing of a Jewish center in Buenos Aires that killed 85 people.
MOHAMMAD BAGHER QALIBAF: Tehran mayor and former commander of the Revolutionary Guard during the Iran-Iraq war. Qalibaf, 51, is a pilot who enjoys good relations with Khamenei.
HASAN ROWHANI: A former nuclear negotiator and Khamenei's representative at the Supreme National Security Council, which also handles the nuclear dossier. Rowhani, 64, is a British-educated cleric. It is possible Rowhani could drop out of the race and throw his support behind Rafsanjani.
ESFANDIAR RAHIM MASHAEI: A top adviser to Ahmadinejad. His candidacy is being heavily promoted by Ahmadinejad, but he will face serious hurdles during the vetting by the Guardian Council, which must approve all candidates. Mashaei, 52, was denounced as a leader of a "deviant current" in Ahmadinejad's political showdown with Khamenei. Mashaei's daughter is married to Ahmadinejad's son.
MOHSEN REZAEI: Former chief commander of the Revolutionary Guard. Rezaei, 58, ran for president in 2009, but finished fourth. He is currently the secretary of the Expediency Council, of which Rafsanjani is chief and which mediates between the parliament and Guardian Council.