Iran's former chief nuclear negotiator and presidential candidate Hassan Rouhani waves to his supporters during a campaign rally in Tehran, capital of Iran, on June 1, 2013. Iran's 11th presidential election is scheduled for June 14. (Xinhua/Ahmad Halabisaz)

Iran's former chief nuclear negotiator and presidential candidate Hassan Rouhani (2nd R) waves to his supporters during a campaign rally in Tehran, capital of Iran, on June 1, 2013. Iran's 11th presidential election is scheduled for June 14. (Xinhua/Ahmad Halabisaz)

Iran's former chief nuclear negotiator and presidential candidate Hassan Rouhani speaks to his supporters during a campaign rally in Tehran, capital of Iran, on June 1, 2013. Iran's 11th presidential election is scheduled for June 14. (Xinhua/Ahmad Halabisaz)