Although Iranian street protests attract attention, a more significant venue for change may be the Majlis (parliament), where the balance of forces reputedly leaves great room for coalition building.
The most obvious question concerns the accuracy of the above data. Indeed, the numbers, perhaps impossible to ascertain with certainty, seem questionable if for no other reason than the fact that they seem to lump supporters of Khamenei in with supporters of Ahmadinejad. Revolutionary-generation clergy represent a very different group than the "neo-con" war generation of national security specialists. Comparing this report with this one (both from just before the recent presidential election) suggests the difficulty of figuring out the real level of Majlis support for Ahmadinejad. In any case, the answer may well be less important than the main point: unless totally inaccurate, the above data imply great potential instability and room for building a compromise coalition. The effort that speaker Larijani has been making publicly to distance himself from Ahmadinejad in recent weeks underscores the conclusion that room for political deals exists in the Majlis.
But Does the Majlis Matter? Even in democracies with strong legal foundations, the role of the legislature can be more smoke than fire and, in fact, easily fade almost out of sight. The spineless behavior of the Democratic Party in the U.S. Congress during the Bush-Cheney years is perhaps the most obvious case in point. In Iran, the undemocratic clerical superstructure that sits on top of not only the legislature but also the executive makes it significantly more difficult for the legislature to take significant action. The apparent high degree of support from this clerical superstructure for Ahmadinejad further constrains the Majlis.
On the other hand, the existence of extended street protests and the recent signs that the clergy itself is split offer the Iranian legislature a rare opportunity to weigh in at a critical moment in Iran's political development. Whether under the Islamic Republic, the dictatorial Shah, or his perhaps even more dictatorial father, legislative initiative has typically played second fiddle to the powerful leader in Iran. The main exception to this pattern was Mossadeq, whose early 1950s effort to bring parliamentary democracy into its own in Iran was destroyed by a coup fomented by a self-serving coalition of the U.S., Great Britain, and members of the Iranian clergy.
Multi-level Political Conflict. Iran's future is being contested at several levels, including very public mass action in the streets, very private maneuverings in the national security organs, and the clergy (note both the twists and turns of Khamenei and the appearance of clergy in street protests).
The involvement of the national security agencies is hinted at by Rezaei's protest followed by his withdrawal of that protest and by rumors reported by international media but denied by Fars News Agency that Islamic Revolution Guards Corps Commander General Ali Fazli had been fired for refusing to repress demonstrations, allegedly goes back to the moment of the election (and even before):
One hour after voting had ended on June 12, Iran’s Interior Ministry had called Mousavi’s headquarters to inform him that he was going to win, and that he should prepare his victory statement without boasting too much, in order not to upset Ahmadinejad’s supporters. But suddenly everything changed. Several commanders of Iran’s Revolutionary Guards (IRG) showed up at Mousavi’s headquarters and told him that his campaign was tantamount to a "velvet revolution," which they would not allow to succeed.
Within this frenzy of maneuvering and second guessing, keep an eye on the Majlis.
On the make-up of the Majlis, see this report on the most recent parliamentary election, in 2008.