Iran will, today, head to the polls to elect its 12th President. Mr Hassan Rouhani, 68, a moderate cleric who negotiated a landmark nuclear deal with world powers in 2015, is standing against three other candidates. <br/><br/>His main challenger is seen as Ebrahim Raisi, 56, a hardline cleric and former prosecutor who is close to Supreme Leader Ayatollah Ali Khamenei. Rouhani seeking a second term.The results may become clear as soon as the next day. <br/><br/>If no candidate takes more than 50%, however, a runoff between the top two finishers will be held May 26th.