Khamene'i and Montazeri
Montazeri was close to revolutionary leader Ayatollah Ruhollah Khomeini during the 1980's, and a strong proponent of his version of the Islamic Republic. He was considered Khomeini's preferred successor until the late 1980's, when he became increasingly critical of the use of force against dissidents. Khomeini denied this was taking place, either for cynical reasons or because by his late 80's he was detached from day-to-day affairs and in denial over what had become of his experiment. As a result, he was fell from favor, and was forced to resign in March 1989. Shortly thereafter, and shortly before his death, Khomeini signaled that his new preferred heir was then-President Ali Khamene'i. Khamene'i did not have the proper clerical credentials, and it required a massive PR move to win some acceptance of him as an ayatollah. This is considered by many to have touched off one of the worst waves of "title inflation" in the Shi'ite world, which has devalued once-august designations and led to the creation of new ones, with "Grand Ayatollah" being the most recent.
After Khomeini died that June, the Assembly of Experts met and duly selected Khamene'i as his successor. Partly to enhance his status, however, they adjusted his titulature. In the constitution, the word "supreme" was inserted before "rule of the jurisprudent," and the same followed in the popular use with "Supreme Leader" gradually replacing just "Leader." Montazeri and many others objected to this change and its implications, as well, for which they were harassed and Montazeri eventually placed under house arrest. Khamene'i continued to accrue religious flattery, particularly when Ali Larijani was head of the state broadcasting company.
There's an additional angle that occurred to me while writing this, and that is that Ali Akbar Hashemi-Rafsanjani, who moved from Speaker of Parliament to President in 1989, was rumored to prefer a council of jurists to a single powerful Leader. If he is, in fact, in Qom politicking among the Assembly of Experts to potentially remove Khamene'i, the issue of what to do after him will come up, and that may be a factor.
(Crossposted to American Footprints)