If one candidate fails to win 50 per cent majority, there will be a run-off between the two front-runners. Mousavi has promised to change the country's economic structure and end Iran's international isolation. His decision to contest the presidential election was welcomed by trade unions and grass-roots activists. Can he win? Watch this space.

 

Image: Hossein Mousavi flashes a victory sign after casting his vote with his wife Zahra Rahnavard in Teheran.
Photographs: Reuters