TEHRAN, Iran - Iran began registering potential candidates Saturday for March 2 parliamentary elections, a vote that will be especially hard fought between supporters and opponents of President Mahmoud Ahmadinejad within the conservative camp.

Iran's major reformist groups are staying out of the race, contending that basic requirements for free and fair elections have not been met.

In their absence, the poll for the 290-seat assembly is likely to pit hard-line candidates who remain staunchly loyal to Supreme Leader Ayatollah Ali Khamenei against conservatives who back Ahmadinejad.

Whatever the outcome, the vote is unlikely to change Iran's course. It is a theocracy, and Khamenei has final say on all state matters.

The March 2 elections will be the first nationwide balloting since Ahmadinejad's disputed 2009 reelection, which the opposition said was heavily rigged. That vote set off months of protests in which hundreds of thousands took to the streets in support of opposition leader Mir Hossein Mousavi, who they said was the rightful winner.

The wave of protests was the biggest challenge to Iran's clerical leadership since it came to power in 1979. But a heavy crackdown suppressed the protests, and many in the opposition were arrested. The opposition has not been able to hold a major protest since December 2009.

In the 2008 parliamentary elections, the hard-line constitutional watchdog known as the Guardian Council, which must approve candidacies, disqualified thousands of reformists.