Many in Tehran boycotted the vote

The conservative rivals of Iran's President Mahmoud Ahmadinejad are set to win parliamentary elections.
 
Officials say more than half the population of Tehran voted in Friday's poll.
 
They say it's the highest turnout for the capital in more than 30 years.
 
But many others decided not to take part.
 
Al Jazeera's Zeina Khodr investigates why.