Six candidates are vying to replace Mahmoud Ahmadinejad in Iran’s 17th presidential poll.

About 50 million Iranians go to the polls today, June 14, 2013, in the first round of voting to elect a replacement for President Mahmoud Ahmadinejad who is not eligible for a third consecutive term after eight years in power, BBC said.

Though eight contenders made it through the rigorous vetting process that eliminated 678 hopefuls, two subsequently dropped out.

The main election issues include the economy that has been hard-hit by years of Western sanctions, the country’s nuclear programme and relations with the rest of the world. If no candidate wins 50.1 per cent of the vote in the first round, a run-off will be held on June 21, 2013 between the top two candidates. The Supreme Leader, Ayatollah Khamenei will ratify the vote on August 3, 2013 before the new President takes the oath in Parliament.

The six candidates running in today’s poll are SaeedJalili, Mohammad BaqerQalibaf, Ali Akbar Velayati, Hassan Rowhani, Mohsen Rezai and Mohammad Gharazi. SaeedJalili is Iran's top nuclear negotiator. Born in 1965, Dr Rowhani joined the paramilitary Basij Force and served in the Iran-Iraq war during which he lost his right leg. Mohammad BaqerQalibaf, 54, is Mayor of Tehran. Qalibaf served as head of the Air Force wing of Iran's elite Revolutionary Guards. A qualified pilot, Qalibaf is also a lecturer at Tehran University.

Ali Akbar Velayati is Ayatollah Khamenei’s longstanding advisor on international affairs and Iran's longest-serving minister since the 1979 revolution. He is also Secretary General of the World Assembly of Islamic Awakening. Born in 1945, Velayati is a qualified medical doctor who served as Deputy Health Minister and then Foreign Minister for 16 years. Hassan Rowhani, a 64-year-old cleric, was Deputy Speaker of Parliament and a chief negotiator in nuclear talks with the EU. He currently heads the Expediency Council's Strategic Research Centre.

Major General Mohsen Rezai on the other hand is Secretary of the Expediency Council. He served for over 15 years as commander of the Islamic Revolution Guard Corps. The holder of a doctorate degree in Economics from Tehran University was born in 1945. Mohammad Gharazi who was born in 1941 and read engineering in Iran and France. He was Minister for Oil and later Telecommunications; as well as being Governor of Khuzestan and Kordestan provinces.