By Frances Harrison
BBC News, Tehran
Haji Mirza Saeed Agha has tears in his eyes as he sings a mournful song at the grave of his two sons who died in the Iran-Iraq war.
Mahmoud Ahmedinejad is seen as a champion of Iran's poor
One went to the front aged only 14. Their innocent faces stare out from black and white photographs placed in glass cabinets above the gravestone.
Haji Agha and his wife come here every week without fail.
"The poor of this country love the Revolution and will shed every last drop of blood for it," he says.
In Friday's run-off vote in Iran's presidential election, Haji Agha is going to vote for Tehran's hardline mayor, Mahmoud Ahmedinejad.
"He is a decent guy, pious, God fearing and a good individual," he explains, adding that Mr Ahmedinejad has risen from the people and understands the pain of the poor.
A week ago political analysts did not rate Mr Ahmedinejad as a serious contender for president - he was an unknown quantity.
Now this ultra-hardliner is trying to appeal to the poor as a man of humble origins who will revive the spirit of the Islamic Revolution.
To his opponents, Mr Ahmedinejad is a dangerous extremist who will roll back social reforms and bring in a more austere interpretation of Islam.
His fiercest critic, Mehdi Karroubi - who lost the first round of elections - described him as an Iranian "Taleban".
Rafsanjani supporters have been noted for fashion sense
Haji Agha is a local commander for the basij - an Islamic volunteer force attached to the mosques.
It is been alleged by three candidates in the polls that the basiji were ordered to vote en-masse for Mr Ahmedinejad as part of an organised attempt to rig the polls.
Haji Agha insists that nobody ordered them to vote for any particular candidate.
"The election was completely free and fair," he says.
But at Basij Day, which is celebrated once a year, it is clear that the Islamic militia is well armed - troops march in chemical war suits and gas masks, fly helicopters and drive tanks.
And they shout death to America - keeping alive the slogans of the hardliners while reformists these days shout: "Free the political prisoners."
It is Iran's most famous political prisoner Akbar Ganji whose picture adorned the wall of the reformist newspaper Eqbal.
Shortly after we went to visit their offices they were closed down for good because they had planned to print a letter criticising the involvement of the basij force in the election.
"Almost I would say this is the first time that these allegations of rigging have been raised," says Karim Arqandehpour, the editor of Eqbal.
Despondency at reformist newspaper Eqbal after it closed
But Mr Ahmedinejad's supporters probably won't mourn the loss of yet another reformist newspaper.
His television advertisements show women in black chador sitting separately from men - a far cry from the trendy young girls in colourful headscarves and skin tight coats who have been out on the streets campaigning for his rival, Akbar Hashemi Rafsanjani.
The message is this is a man who will address the problems of young Iranians - not those who want to party and embrace Western culture but those who still feel dispossessed and need jobs.
Mahmoud Ahmedinejad says what makes him different is that he does not have the backing of big business.
"If the people pay for the costs of my election campaign then it means I am a popular candidate," he says. "All my expenses have been met by the people".
Speaking about justice and clean government has won Mr Ahmedinejad support among those who feel the Revolution benefited a few and failed to deliver to the masses. From having an outside chance of success last week, he is now a serious contender for president.