TEHRAN, Iran — Tehran's Vali Asr Street, the Iranian capital's longest, was a torrent of green as youths by the thousands paraded past, holding green posters, sporting green ribbons on wrists and car antennas and drinking green fruit drinks. Their choice of color was a proclamation of support for Mir Hossein Mousavi, the candidate who suddenly seems to have a chance of ousting President Mahmoud Ahmadinejad.
The raucous rally Monday night for Mousavi, a former prime minister, had the air of a street fair, out of place in the usually staid Islamic Republic of Iran. Some residents described it as one of the largest unofficial gatherings since Iran's Islamic revolution 30 years ago.
Not everyone was impressed. Ahmad Abbasi, who was watching from curbside, dressed in short sleeves, jeans and sandals, described Ahmadinejad, who's widely reviled in the West, as simple, honest and humble.
"It takes a lot in a person to not see himself as president, and to have the humility to bring himself down to my level," said the 43-year-old shipbuilder, recalling the time he met Ahmadinejad. "This is why I respect the man."
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With a vote watched around the world set for Friday, Iran's presidential campaign has suddenly morphed into a bitter referendum on Ahmadinejad. Unprecedented personal attacks have erupted, the first-ever televised debates have been held and political rumors abound.
In the process, the election has exposed deep social fault lines in this country of 66 million, which is one of President Barack Obama's toughest foreign-policy challenges.
On one side are the mostly young, urban and educated Tehranis who poured into the streets Monday night, hoping that Mousavi — who's remembered for managing Iran's economy during the 1980-88 war with Iraq — would reverse this oil-rich country's steep price increases and high unemployment.
On the other are many of the working-class men and women, war veterans and rural Iranians who take pride in Ahmadinejad's simple ways and thumbing of his nose at the West.
So Iran's president is, depending on which Iranian you talk to, a national embarrassment who dispenses blather about the Holocaust and frittered away the country's oil earnings during the peak of world oil prices, or an honest man of the people.
"He spent the oil money and he gave it to the people for potatoes," said Mousavi supporter Mehrdad Biglarbegian, 23, green face paint adorning his cheekbones. He referred to Ahmadinejad's frequent trips to the provinces, where he has, in fact, distributed sacks of potatoes and other largesse.
There are two other candidates in the race: Mohsen Rezaei, a former commander of the Islamic Revolutionary Guard Corps, who doesn't appear to be garnering deep support, and former parliament Speaker Mahdi Karroubi.
Karroubi, not leading contender Mousavi, has the real reformist platform in the race. He's called for changes in Iran's Constitution, more rights for women and minorities and better relations with the United States. At a heated rally of his own Tuesday evening — at which some in the crowd held pictures of political prisoners — Karroubi denied rumors that he'd step aside in order to help Mousavi win.
If no candidate wins 50 percent of the vote Friday, the top two vote-getters will compete in a run-off June 19.
Despite the veneer of Western-style politics, an Ahmadinejad defeat — and no incumbent has been defeated since the revolution — wouldn't bring sudden change to Iran or its non-relationship with the United States.
Iranians are quick to point out that the president is the "No. 2 leader," after supreme religious leader Ayatollah Ali Khamenei, who has final say on most matters, including Iran's suspected nuclear-weapons program. That program isn't a major campaign issue.
Mousavi, an architect, isn't a firebrand reformist, and many young people remember the tenure of former President Mohammad Khatami. Khatami promised change, but he proved unable to stop a regime crackdown on students who took to the streets in the late 1990s demanding that he implement his promises.
Mousavi is no different from other politicians, said Faezeh Falleh, 23, who was holding a sign that said "No Lies" in Farsi. Falleh won't vote Friday. "It doesn't matter who wins," she said. The election "is a game (of Iran's religious leaders), I think."
Whether the balloting will be fair is another question. Analysts in Washington and Tehran are betting that Ahmadinejad would "win" a close race, but that authorities wouldn't intervene if he were losing in a blowout.
"Iranian elections have the unique combination of being unfree, unfair and unpredictable," said Karim Sadjadpour of the Washington-based Carnegie Endowment for International Peace.
Ahmadinejad was once again the center of controversy Tuesday, and he may have faced a new setback, when former President Hashemi Rafsanjani publicly asked Iran's supreme leader to intervene after Ahmadinejad leveled financial-corruption charges against him.
Ahmadinejad startled many Iranians by making the accusations against Rafsanjani and other leaders during a televised debate with Mousavi last Wednesday.
Rafsanjani called the charges "unfounded and irresponsible," as well as un-Islamic, in a letter to Iran's supreme leader, according to the quasi-official Mehr news agency.
Ahmadinejad can count on the support of Iran's vast security establishment, however, as well as of voters such as Reza Khalkhali, a 41-year-old war veteran who displayed a bullet wound on his leg and a shrapnel cut under one eye.
"I haven't met anybody as sincere and honest as this guy," Khalkhali said at an Ahmadinejad campaign event at Tehran's unfinished Grand Mossala mosque. Factory owner Asghar Jasbi, 55, chimed in, calling Mousavi's supporters "spoiled brats" from well-off north Tehran.
Spoiled or not, Mousavi's youth brigades — and Iran has one of the world's youngest populations — are omnipresent on the capital's streets this week. They honk their horns, jump from cars stalled in the city's horrendous traffic to pass out fliers car to car and their colors are more visible than the red, white and green Iranian flag, which Ahmadinejad has appropriated for his campaign.
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