Iran's conservatives announced a shortlist of five presidential candidates on Thursday as they experimented with their first-ever democratic primary in a bid to find a leader to challenge President Hassan Rouhani.
Fearing another defeat at the hands of the moderate president in next month's election, a new alliance called the Popular Front of Revolutionary Forces hopes to unite conservatives around a single figure.
Some 3,000 delegates gathered at an exhibition centre on Tehran's outskirts to vote for the shortlist.
It includes 56-year-old cleric Ebrahim Raisi. Barely known a year ago, he is the head of a powerful charitable foundation in the holy city of Mashhad and tipped as a possible successor to supreme leader Ayatollah Ali Khamenei.
Also included was Tehran mayor Mohammad Bagher Ghalibaf, 55, who came second to Rouhani in 2013.
The others were Parviz Fattah, head of another charitable foundation, and former lawmakers Alireza Zakani and Mehrdad Bazrpash, both fierce critics of the 2015 deal with world powers that saw sanctions eased in exchange for curbs to Iran's nuclear programme.
All five will register as candidates, but four will drop out shortly before the election on May 19.
- 'Not well-known' -
Raisi has gathered considerable momentum in recent months, but his selection was ridiculed by reformists.
"It shows they have reached an impasse and been defeated. They have been forced to choose a non-politician," reformist commentator Abbas Abdi told the Etemad newspaper.
"Mr Raisi is not a well-known -- or even known -- political figure."
Ghalibaf, an experienced pragmatist, has strong conservative credentials: during the last campaign he boasted of riding through crowds of student protesters in 1999 on a large motorbike, beating people with a stick.
"Ghalibaf is the top candidate. His management style is the best," said one of Thursday's delegates, 25-year-old clerk Nastaran Danehkar.
But analysts say his chances have been hit by allegations that Tehran city councillors were given prime real estate at knock-down prices.
- Spoiler -
Keeping Iran's conservatives united will prove tough.
A familiar spoiler has already emerged in the form of ex-president Mahmud Ahmadinejad, who announced on Wednesday that he was backing his former deputy Hamid Baghaie as an independent.
Ahmadinejad ruled out his own comeback last year after the supreme leader suggested it could have a "polarising" effect on the nation, but his chosen successor could steal conservative votes particularly in poorer areas.
Some at the exhibition centre said the new nomination process was more important than winning.
"In the past, a few elders would sit and come out with some choices, but now it has become a process like a referendum where forces at the bottom can influence the final decision," said Abdolhossein Moslemi, a cleric.
Tehran-based political expert Amir Mohebbian agreed that "the old mechanisms had failed".
Since the 1990s, he said, the choices by conservative grandees have lost every time -- either to more reformist candidates, or in the case of Ahmadinejad, to a hardline populist who refused to play ball with the establishment in a way that many have lately compared to Donald Trump.
- Solid alliance -
By contrast, Rouhani's alliance of moderates and reformists looks solid, even if continued economic problems and Trump's threats to reimpose sanctions have cast doubts over his strategy of reaching out to the West.
Reformists see little alternative to Rouhani, having been badly damaged by a crackdown following protests in 2009.
Two of their leaders -- Mehdi Karroubi and Mir Hossein Mousavi -- have been under house arrest since 2011, while the media are banned from picturing or quoting former reformist president Mohammad Khatami.
The key moment will come later this month when the powerful Guardian Council chooses who will be allowed to run.
"Rouhani is still the most likely candidate," said Henry Smith, of consultancy Control Risks.
"If he chooses to run, and is allowed to run, we can assume he has the blessing of the supreme leader to go for a second term."