The gloves finally came off on Iranian National Television, during the first live TV debate held between candidates for president of the Islamic republic.

It was on June 4 that a former prime minister of Iran, Mir Hossein Mousavi, now considered the frontrunner for today's presidential elections, accused incumbent President Mahmoud Ahmadinejad of tainting the country's image by questioning the Holocaust and thereby damaging Iran's credibility.

He also accused Ahmadinejad of maintaining a reckless style of leadership that has caused many of the world's leading powers, as well as some of Iran's natural allies, to sideline the country on the regional and international stages.

This kind of verbal jousting is unusual in Iran's Islamic theocracy.

But it does indicate that, despite the attempts by Iran's Shiite clergy to control the outcome of this election by declaring that several reformist minded candidates are ineligible to run for the presidency, elements of reform are back.

Readers would recall that in 2005 the Iranian regime had more or less wiped out the reformist camp.

This was done by systematically assassinating and imprisoning intellectuals who were central to that camp, and by ensuring that reformist leaning politicians like past president Mohammad Khatami would not be allowed to qualify as a candidate for the top job.

When today's election was called, there were initially 475 presidential candidates. That number has been winnowed down to the point where only four prominent candidates were able to survive the rigorous screening conducted by the Islamic Guardian Council.

Those four are: Ahmadinejad, who is still seemingly the favourite of the radical messianic elements within the conservative faction headed by Iran's Supreme Spiritual Leader, Ali Khamenei; Mousavi, former prime minister and member of the revolutionary old guard that helped to bring the Ayatollah Khomeini to power in the 1979 Islamic revolution which overthrew the Shah;Mohsen Rezai, a former commander of Iran's Islamic Revolutionary Guards Corps; and, Mehdi Karroubi, a former speaker of the 290-seat Iranian parliament, or Majlis.

Of these four high-profile candidates, the race is likely to boil down to a sprint between Ahmadinejad and Mousavi. In fact, several knowledgeable observers of Iranian politics-- including one of my Iranian colleagues at the University of Alberta, Dr. MojtabaMahdavi-- are predicting that today's election will result in a run-off. The minister of the interior has already set June 19 as the date for the official run-off --a second round of elections that will be held if no candidate is able to muster more than half of the eligible votes cast today.

Of the country's 70 million people, about 46.2 million Iranians are eligible to vote in this election. Given the excitement over the possibility that there could be a change in leadership, the turnout at the polls is expected to be very high. Even Iranians living abroad are intent on having a say in this year's elections. There are 304 polling stations set up outside Iran, including 32 in the U. S.

It is evident from following the campaign that Ahmadinejad has lost the support of much of the conservative establishment in Iran. This could hurt his chances.

Ahmadinejad is a populist who used his popularity as a former mayor of Tehran to catapult himself to power.

But to remain in the position of president, Ahmadinejad needs to have the support of the moderate and traditional conservatives.

He has more or less alienated the moderate conservatives (the traditional ayatollahs, the bazaar merchants, and those that have done well economically, like the still influential former president, Ayatollah Ali Akbar Hashemi Rafsanjani.

But Ahmadinejad's fate could be decided by the youths of Iran, many of whom boycotted the last presidential elections.

It is unlikely that the young people of that country, who constitute about 20 per cent of the electorate, will stay at home today. There is an anti-Ahmadinejad mood sweeping across university campuses in Iran.

Many of the Iranian youths are fed up with the harsh restrictions being placed on them by religious leaders.

Bear in mind that an increasing majority of the youth in that country were not born at the time of, or have no memory of, the 1979 Islamic revolution. These individuals are more likely to support the reformist-minded candidates in this election.

And Mousavi is likely to be the beneficiary of their support.

W. Andy Knight is professor of international relations at the University of Alberta, and a governor of the International Development Research Centre (IDRC) in Ottawa