Iranians vote today to elect a new Majlis, the 290-seat parliament, but there's little real choice on the ballot and little chance that the outcome will defuse dangerously hostile relations with America over the Islamic regime's nuclear program.
But with oil prices spiking, Israeli leaders openly musing about pre-emptive attacks, neighbouring Syria sliding into full-blown civil war and the memory still fresh of the 2009 post-election protests in Tehran, any political spark in Iran could trigger a conflagration.
Unpopular and discredited President Mahmoud Ahmadinejad is not on the ballot. Presidential elections aren't until next year. But the composition of the new Majlis may embolden the theocracy, giving it at least the appearance of public support.
"It's guaranteed not to be free and fair," warns Reza Marashi, research director at the National Iranian American Council. "It's about warring conservative factions who have purged the reformists."
What's at stake is which of the feuding, conservative, theocratic factions emerges empowered. Reformists have been "beaten, banned or driven into exile," Mr. Marashi said.
So there's scant chance of a repeat of the rigged 2009 presidential elections that returned the wily and unpredictable Mr. Ahmadinejad to office but did set off eight months of bloody street demonstrations.
The brutal crushing of pro-democracy moderates was the worst internal violence since the 1979 Islamic Revolution toppled the Shah and transformed a tame Western ally into a powerfully hostile regime poised to challenge the "Great Satan" in the region.
For Tehran's ruling mullahs, especially, Supreme Leader Ali Khamenei, the vote offers a chance to re-assert the legitimacy of the regime.
Iran's pro-regime media have been touting turnout expectations of about 60 per cent, suggesting broad support for rival conservative factions will prove the mullahs still enjoy widespread backing although reformers and opposition are non-existent on the ballot..
But with key reform leaders still under house arrest and opposition candidates mostly barred from running or boycotting the election, the call has gone out urging ordinary Iranians to stay home.
The lower the actual turnout, the more the regime will need to rig the appearance of Iranians voting.
The more Iranians vote, the more the regime will be able to claim legitimacy and backing, especially for the nuclear program, which bedevils Tehran's relations with the region and the rest of the world.
"Therefore, the election officials are more or less forced to fabricate a result that fits the predictions of the Supreme Leader," said Ali Alfoneh, an Iran expert at the American Enterprise Institute.
If Iranians had any doubts about what's expected of them when they mark their ballots – and every citizen's identity card is marked to show whether he or she voted –Ayatollah Khamenei made the required outcome clear in a speech on the eve of the election.
"With the grace of God, the Iranian nation will give the global arrogance and forces of imperialism a slap in the face in Friday's election," the 72-year-old ruler said, in a clear reference to the United States and Britain.
In the murky, Byzantine world of Iranian domestic politics, most see the election as a battle among rival conservative groups for pre-eminence.
Mr. Alfoneh described three main factions of conservatives: one lined up behind parliamentary speaker Ali Larijani; another supporting former parliamentary speaker Gholam-Ali Haddad Adel, who is the father-in-law of one of Ali Khamenei's sons, Mojtaba Khamenei; and a third group called the Islamic Resistance Front.
But he said Iranians generally view them as "krypto-Ahmadinejad supporters" who set themselves up as his critics for tactical reasons.
Already estranged from Ayatollah Khamenei and widely blamed by Iranians for soaring prices and a flagging economy, President Ahmadinejad seems likely to be further damaged and sidelined by the Majlis election.
"Ayatollah Khamenei is guaranteed to be the winner," said Mr. Marashi, although he cautioned that there could be unexpected consequences.
Although the opposition is demoralized and weakened, with its leaders in jail or in exile, the sweeping tumult of change that has toppled regimes across the Arab world has created a new and unpredictable dynamic in the region.
Three years ago it was impossible to know that the hundreds of thousands of chanting, pro-democracy demonstrators that thronged Tehran's streets were a harbinger of massive change continuing today across the Muslim world. While the mullahs crushed the Green movement in 2009, the Arab Spring has proved that no regime, no matter how ruthless, is secure.
"The powers that be will use the election to further fence in the opposition," said Rex Brynen, a Middle East expert at Montreal's McGill University.
An estimated 48 million Iranians are eligible to vote. More than 3,440 candidates – all between 30 and 75 years of age – were approved but the Guardian Council, a group of senior mullahs that vets candidates, disqualified more than 2,000 others.