What were expected to be fairly sanitised presidential elections in Iran were dramatically disrupted last week by former president Mahmoud Ahmadinejad's decision to put himself forward as a candidate. His decision to enter the race is a direct rebuke to the country's supreme leader, Ayatollah Ali Khamenei, who last September advised Ahmadinejad not to run in the elections scheduled for 19 May. The move has been widely interpreted as a political gimmick designed to contrive a drama rather than a serious attempt to win. Despite his eight-year term in office as president, Ahmadinejad is unlikely to get the approval of the Council of Guardians that all the candidates must have by law in order to run. In the unlikely event that he does get the green light from the Council, Ahmadinejad will likely radicalise positions on all sides and pose a credible threat to the incumbent President Hassan Rouhani, who is also standing for re-election. Moreover, his dramatic entry into the race speaks to the wider weaknesses of the Iranian electoral system. While campaigning methods in Iran get more sophisticated with every electoral cycle, the underlying system hinders a disciplined approach towards an individual's candidacy. In the absence of strong and established parties in Iran, the initial phase of the elections, being the registration of the candidates which began last Tuesday and was set to close on Saturday, has been marked by a degree of randomness and in some cases absurdity. With minimal financial costs to enter, hundreds of ordinary people with no political background have been rushing to register for the race. Needless to say, all of them are subsequently disqualified by the Council of Guardians. It is this chaotic system that naturally suits political agitators such as Ahmadinejad, who is set on provoking the establishment. More broadly, it also appeals to an electorate with a proclivity to produce surprises at the polls. Iran's idiosyncratic electoral system is more of a natural by-product of the country's political culture than a carefully crafted mechanism. There are also no insurmountable institutional obstacles stopping people from forming strong political organisations. Yet, the existing political parties are invariably weak, with ill-defined procedures and hierarchies and little connection to the grassroots they are meant to represent. As a result, makeshift movements emerge in every electoral cycle to galvanise supporters on either side of the country's main political divide, namely that between reformists and conservatives. It is into this chaotic mix that Ahmadinejad has now entered, having earlier been expected to make a splash in the elections, although indirectly. Few thought he would dare to disobey Khamenei, but many thought he would try to stir the pot through his protégé Hamid Baghaei, who has also registered his candidacy. Sure enough, after he entered the race Ahmadinejad said that he had done it in order to support Baghaei, a claim lent credence by the two men's joint campaigning, most recently among the influential Bakhtiari tribes of southwestern Iran. Ahmadinejad's controversial right-hand man Esfandiar Rahim Mashaei also nearly always appears with the two candidates in public, giving the impression that they are running an organised electoral movement with staying power. In view of the Iranian establishment's disdain for these men, however, now regarded as a “deviant current,” it is unlikely that even Baghaei will be cleared by the Council of Guardians to stand in the elections. This means that the key question at this juncture is what Ahmadinejad and his circle hope to gain by provoking the establishment. Their motives are likely to be many, and Ahmadinejad has a strong constituency, meaning that there is a clear demand for his continued presence on the political scene to balance out other forces. The wider electoral picture also provides further clues as to Ahmadinejad's motivation. In keeping with a tradition dating back to 1981, the incumbent president is widely expected to secure a second term. Thus far, his strongest challenger is Ibrahim Raisi, the custodian of the Imam Reza Shrine in Mashhad and by extension the vast business empire attached to it. A close ally of Khamenei, Raisi was earlier being touted as his potential successor. The conservatives in Iran have not held the country's presidency since 1989, in part because of internal divisions and their inability to rally around a consensus candidate, and it remains to be seen if Raisi can form a solid consensus in the run-up to the polls. The wider electoral picture also does not look promising for other Rouhani opponents who are likely to include political lightweights such as former telecommunications minister Mohamed Gharazi, a candidate in the 2013 presidential race, and Tehran mayor Mohamed Bagher Ghalibaf, who also ran in 2013. Ghalibaf has yet to register for the race, but he is expected to do so shortly. In the last presidential race in June 2013 he came a distant second with just over 16 per cent of the vote, and he is unlikely to perform any better this time round. Entirely disowned by the conservative establishment in Iran, Ahmadinejad and his inner circle can best be described as maverick principlists. The principlist (osoolgera in Farsi) current in the Islamic Republic is widely considered to be an extension of the conservatives, despite important political differences between the two groups. More of a principlist than a conservative stalwart, Raisi is considered to be a cross-pollination candidate of sorts. Indeed, the impromptu political organisation that he represents, namely the Popular Front of Islamic Revolution Forces formed late last year, speaks more to radical principlist attitudes than conservatism. At a national level, the conservatives/principlists face a broad but relatively cohesive reformist and centrist coalition in the elections. This divide has been a defining feature of Iranian politics since 1997, with Ahmadinejad's presidency (2005-2013), especially his second term, considered an aberration. Ahmadinejad is now trying to stake out a political future as a third force in Iranian politics. He represents a principlist movement that is distinctly different from other conservative and even other principlist factions. Even if, as expected, he and Baghaei are disqualified from this year's race, Ahmadinejad nevertheless hopes to build a credible platform from which to contest future elections. It remains to be seen to what extent the Iranian establishment can co-opt this insurgent movement. The writer is an analyst of Iranian politics and director of the research group Dysart Consulting.