Hundreds of thousands of chanting, cheering Iranians turned out to support Mir Hossein Mousavi in Tehran yesterday. The former Prime Minister has become the great hope of millions of his compatriots who yearn for freedom, prosperity and normal relations with the world. He is, however, an unlikely vessel for so much ambition.

Mr Mousavi, 67, is no Lech Walesa or Vaclav Havel, no Nelson Mandela or Mahatma Gandhi bent on destroying an evil regime. He is, and has been, a part of the Iranian regime throughout its 30-year history.

He is cautious, a dull campaigner and an uninspiring speaker, but he happens to be much less hardline than Mahmoud Ahmadinejad. He also has a magnificently feisty and much more liberal wife, Zahra Rahnavard.

Friends say the pair met when they were followers of Ali Shariati, a dissident Islamic philosopher in the time of the Shah. Both were actively involved in the Revolution of 1979. He then served as Prime Minister of the new Islamic Republic, and from 1981 to 1989.

None of Iran’s legions of younger voters remember that period. They are told he managed the economy very competently during the Iran-Iraq, but older Iranians say his government tolerated little dissent. During the televised debates before last week’s elections Mr Ahmadinejad accused him of being responsible for a massacre of political prisoners.

After the Prime Minister’s post was abolished, Mr Mousavi retired from active politics, though he remained a member of two high-level regime councils. For the next 20 years he dedicated himself to painting, architecture and his three children. He designed a number of prominent buildings in Iran, and his post-modern paintings sell for considerable sums.

Mr Mousavi refused to stand for president in 1997, clearing the way for Mohammed Khatami, a reformist who won by a landslide. In this month’s election Mr Khatami made way for Mr Mousavi, who said he was running because Mr Ahmadinejad’s presidency was a “danger” to the country.

His candidacy had to be approved by the Guardian Council, a body of 12 senior and conservative clerics who vet all prospective candidates to ensure they support Islamic principles and revolutionary values. Of more than 470 applicants it let just four stand.

Mr Mousavi campaigned on a less than inspiring platform of competence and stability. He called for greater social freedoms, economic liberalisation and constructive engagement with the West, but he was careful not to go too far because he was anxious to win the votes of conservatives disenchanted with Mr Ahmadinejad as well as moderates.

He said he would “review” laws that discriminate against women, and would try to disband the reviled morality police. He was prepared to talk to President Obama under certain conditions.

He insisted on Iran’s right to pursue nuclear power for civil energy, but said its use for weapons was negotiable. His most memorable soundbites were to accuse Mr Ahmadinejad of “exhibitionism” and “sensationalism” in foreign affairs and reducing an Iranian passports to the value of Somalia’s.

There was a more radical candidate that reform-minded Iranians could have rallied behind – Mehdi Karoubi, a former parliamentary speaker who won five million votes in 2005. Mr Mousavi emerged as their preferred candidate partly because he was endorsed by the popular Mr Khatami, partly because his campaign was fuelled by the money and muscle of the former president Hashemi Rafsanjani, and partly because of his wife.

Dr Rahnavard broke with tradition by actively campaigning for her husband. She held a press conference to denounce Mr Ahmadinejad as a liar, misogynist and betrayer of revolutionary values. She wears colourful clothes, and fights for women’s right. She is everything her husband is not – bold, outspoken, radical and a forceful public performer.

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