This is not to say that all Iranian presidents served two terms.
"The first president, Abolhassan Banisadr, was impeached," the analyst said. "The second president, Mohammad-Ali Rajai, was killed in a bomb attack in August 1981. Basically since then every president who contested the second term has won. I think it is an important precedent. It speaks to a voting habit of the Iranian electorate. I think they prefer the devil they know to the devil they don't."
The presidential election in Iran is scheduled to take place on May 19. The Guardian Council of the Constitution initially approved a list of six candidates, comprising Rouhani, Vice President Eshaq Jahangiri, Ebrahim Raisi, chairman of the Astan Quds Razavi autonomous charitable foundation, Tehran Mayor Mohammad Bagher Ghalibaf, former Minister of Culture and Islamic Guidance Mostafa Mir-Salim and former Vice President Mostafa Hashemitaba. Jahangiri and Ghalibaf have dropped out of the race.
Abedin suggested that Rouhani, who has been in office since 2013, is likely to win the election.
"Polling does seem to suggest that Rouhani has a lead. He has a better political machine behind him. His campaigning has been more effective because he has got more money behind him. Campaign materials that I have reviewed in the past few days have been terrific, very good. Rouhani certainly has a momentum," he said.
"Raisi is basically the custodian of the Imam Reza shrine in Mashhad," the analyst said. He heads Astan Quds Razavi, "a very important institution not only because it deals with millions of Shia pilgrims who go to the Imam Reza shrine in Mashhad every year from all corners of the Islamic world, but because there is a vast business and charitable empire attached to that foundation. Its estimated revenue is $15 billion a year which is substantial by any standard. It also employs tens of thousands of people."
Abedin described Raisi as the "effective ruler of eastern Iran, certainly Khorasan provinces."
"But for some reason they put [Raisi's] name up for the presidency," he added. "I must say that he performed exceptionally poorly during the campaign process, worse than expected. His performance in the televised debates was extremely poor. He is mild-mannered. He is not really a politician. In fact he has no political background whatsoever. His background is in the judiciary. He is not a particularly good debater."
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