Sitting on his moped in the twilight of central Tehran, Peyman Moghadam was heckling passing cars. Glued to his forehead was a photo of the former Iranian president Akbar Hashemi Rafsanjani.
"There is only Akbar Shah!" the teenager shouted passionately at any motorist daring to display a rival candidate's poster on the last night of campaigning.
Today the 17-year-old will be among the first in line to vote for Mr Rafsanjani who is widely expected to complete an extraordinary political comeback by retaking the office he vacated eight years ago. "When he was in power before, he was extremely powerful," said Mr Moghadam. "He's the only one who can make this country work again."
Young and jobless, like so many other Iranian voters, Mr Moghadam's main concern is the state of the economy and he sees little prospect of elections bringing any real change in the face of a intransigent clerical elite.
The trade-off is a cynical one: his heart wants reform but his head tells him that only an insider, like Rafsanjani, can actually achieve anything. As Iran goes to the polls, the stakes could scarcely be higher. The three political factions represented offer perhaps the greatest degree of choice yet put to the Iranian people. Mr Rafsanjani's supporters say he will create economic growth, solve the festering nuclear problem and achieve rapprochement with the US.
Reformists have meanwhile broken longstanding political taboos by promising to free all political prisoners and challenge the power of the Supreme Leader. Populist conservatives, who call themselves fundamentalists, say they will achieve social justice and reverse an ever-widening wealth gap. And supporters of a boycott are intent on creating a broad democratic front to challenge the entire system of Iran's theocratic state.
In this charged atmosphere, President Mohammad Khatami has warned of dark forces at work: "It seems there is an organised movement to hurt the glorious process of the elections," he said in a letter. He warned of a dirty tricks campaign that involved disrupting gatherings, beatings and slander - a reference to attacks on reformist politicians in recent weeks.
"This is a very different election from those in the past," said a leading Tehran analyst who did not want to be named. "The manner of campaigning has completely changed to accommodate much younger voters and the political wings represented could not be more different."
Even the conservatives have made a clear effort to appeal to younger voters, with poster designs that feature young people and draw more influence from western-style advertising than the religious calls to duty that were made in the past. "Fresh air" - a quote from a famous secular poet - has been adopted as a slogan by an arch conservative.
The cheerful posters are in stark contrast to the dark political realities besetting the Islamic republic. As Western suspicions about Tehran's nuclear intentions grow, the threat of a new sanctions regime or even air strikes against nuclear facilities has come into sharper focus.
Washington has accepted the desirability of reaching a negotiated settlement with Iran but is losing patience with the drawn-out process required to achieve it. And both sides look as far from a compromise as ever on the crucial issue of uranium enrichment. At home, the political battle between reformists and conservatives has left government channels gridlocked, severely impacting on economic policy and causing a hardline assault against dissident political thinkers and publications. Human Rights Watch warned last year abuses were increasing as the conservative religious judiciary fought off a perceived political threat.
Despite the importance of this moment, many people see voting as a waste of time. "It's everybody's duty to vote but they're all from the same gang," said Shahram Rashti in his boat on the reed-banks of Anzali lagoon on the Caspian coast. "There's so much unemployment in the city and politicians only ever make promises." But in recent days, as polls show the leading candidates drawing closer together, more people have said they will vote. As campaign volunteers staged last-minute rallies through the night, the streets were crowded with the committed and the curious, revelling in the buzz of political debate.
Posters, stickers and leaflets littered the ground and young people marched up and down on Tehran's Vali Asr Street, shouting the slogans of their men and thrusting pamphlets through open car windows. One man looked around bewildered by the vast amounts of money that had been spent on all the bumpf - another departure from previous elections. Much of it displayed the familiar features of Rafsanjani, who increasingly uses his family name Hashemi, instead of the moniker derived from his home town by which he is better known. The mercurial front-runner is often criticised by for his supposedly huge personal fortune, and drew ironic donations from students after saying his only income was gleaned from the family pistachio farm.
"It's our destiny and our future so we must vote," said Reza Poshkoni, 27, sipping tea with his fiancée under a sunshade near the Azerbaijan border. "Rafsanjani was the president before so he should do better than the others." With two spells in the job under his belt, Mr Rafsanjani engaged in an extended political tease for months, confirming he would run in May. He has walked tall across Iran's political landscape since early in the revolution and is the last of the Islamic republic's founders to run for its highest elected post. He is popularly seen as the great Machiavellian powerbroker of Iranian politics, a man of backroom deals and shifting allegiances.
His nickname, Akbar Shah (King Akbar), refers to this passion for playing the games of high power as well as the wealth he is rumoured to have accumulated. Now head of the Expediency Council, a body that arbitrates constitutional disagreements, his office is an old palace of the former Shah, where marbled corridors and luxuriant carpets cast the shabbier offices of less brilliant luminaries into the shade.
"I predict that within six months of his presidency, there will be a total understanding between Iran and the West over the nuclear issue," a key ally, Mohammed Atrianfar, told The Independent. "And on the last day of his presidency in four years time, the American embassy will reopen in Tehran."
Despite the increased kudos and real desire to achieve détente that Rafsanjani could bring to the presidency, western diplomats remain sceptical as to whether he can achieve his goals. On the international stage he is shackled by a terrorism charge that could restrict his movement. And at home the increasing bitterness of this election will limit his bargaining power with the hardliners. His last term in office was characterised by the sort of infighting that has come to define the Khatami years. And with a hostile conservative parliament and fundamentalist bodies such as the Guardian Council to deal with, the man from Rafsanjan could find the heady draughts of presidential power come in a poisoned chalice.
Much will depend on his relationship with the Supreme Leader, Ayatollah Ali Khamenei. The two are rumoured to be engaged in a long power struggle over political supremacy in the country. As one ally observed: "Khatami always used to challenge the leader in public and give in in private. But Rafsanjani would agree to everything in private and then do what the hell he liked."
Mr Rafsanjani will likely face a second-round run-off against either Mostafa Moin, a reformist whose popularity has grown rapidly, or Mohammed Baqer Qalibaf, a former police chief and leading fundamentalist candidate. The reformists have been characterised as weak, but Mr Moin has pushed their agenda to new, tougher areas. Besides promising to free political prisoners - a category the judiciary does not recognise exists - he says he will appoint Shirin Ebadi, the Nobel peace laureate, as a human rights minister.
Now garnering support from the Freedom Movement, a dissident party stemming from the great prime minister Mohammed Mossadegh, who was ousted by the Shah in a British-US coup in 1953, the reformists have become more outspoken. One of their chief ideologues, Mehdi Karroubi, said they wanted to change the constitution. But for all the reformist resurgence, the conservatives have remained stubbornly immovable in polls.
"The most important thing about Qalibaf is he is closest to the ideas of the Supreme Leader," said Fatameh Hosseini, a chador-dressed woman at a Qalibaf rally. "The qualities he has will be very important and he can put this country on a different track." If Qalibaf wins today or in the likely run-off a week later, he will bring the presidency into line with the leader, the parliament, the revolutionary guards and the non-elected watchdog offices that control much of the state. And while many senior conservatives know that it is important to keep young people on board, a Qalibaf victory could create a schism between the young and the state.
That's exactly what Laleh Karimi, an English student in a park near Tehran's Modern Art Museum, will hoping to stop. "I wasn't going to vote but then I realised a boycott wouldn't work and I really don't want the country to go back to the conservatives," she said. "I know the reformists won't be allowed to do very much but at least I like what they believe in."
AKBAR HASHEMI RAFSANJANI
Conservative cleric, now 70, served as president from 1989-97. He wants improved ties with the West and insists Iran's nuclear programme is peaceful. Middle-man involved in the Iran-contra arms deal in which the Reagan administration sold arms to Iran in return for help releasing American hostages in Lebanon. Exposed to demands for change through his daughters, including Faezeh Hashemi whose newspaper, 'Zan' was closed by hardliners.
Reformist candidate, 54, who is adviser to the outgoing President, Mohammad Khatami, and a former higher education minister. Chancellor of Shiraz university from 1981-1982, where he was accused of purging dissidents. Could be hurt by student boycott of election, from which he was initially barred by unelected hardliners until the Iranian spiritual leader intervened. Advocates improved relations with Washington, and wants to weaken control of the ruling unelected clerics.
MOHAMMED BAQER QALIBAF
Hardliner who quit as police chief to run in the election. Mr Qalibaf, 43, modernised the force following his appointment in 2000. Has shaved his beard and wears a suit, but his conversion has not been convincing. Unpopular with young voters since it emerged he had backed the crackdown against pro-democracy students in 1999, in which one was thrown from a window to his death.