Unlike Mr. Zhao, who faced only internal sanctions and was confined to his home until his death in 2005, Mr. Bo was expelled from the party and criminally charged. If he accepts a deal with party leaders, he is likely to get a prison term of 15 to 20 years, long enough to destroy his chance of a comeback. But if the unpredictable Mr. Bo defies the court, as Jiang Qing, the widow of Mao Zedong, did in 1980, it could greatly embarrass party leaders, who might order the court to give Mr. Bo a suspended death sentence, tantamount to life in prison.

Mr. Bo’s epic fall is unique among the “princelings,” the children of the revolutionary generation who established the People’s Republic in 1949, many of whom have amassed enormous riches. He is accused of accepting around $3.3 million in bribes, embezzling $1 million and misusing his authority. Mr. Bo’s wife, Gu Kailai, was given a suspended death sentence last August for murdering a British businessman (though evidence of her guilt remains murky). Their son, Bo Guagua, recently enrolled at Columbia Law School, which some observers see as a sign that Mr. Bo has reached a deal with President Xi Jinping, one that would allow the son to stay abroad and to preserve some of the Bo family’s overseas assets, which apparently include a villa in Cannes, on the French Riviera.

But the pretrial proceedings have dragged on for nearly a year, a sign that airbrushing Mr. Bo out of the picture is proving more difficult than anticipated. Mr. Bo’s allies and foes are deeply intertwined. Even the seven-member Politburo Standing Committee — which is led by President Xi and which Mr. Bo once hoped to join — cannot easily move against Mr. Bo’s formidable, though weakened, allies.

Most Chinese know that Mr. Bo, with his flamboyant egotism, was no angel. Under his crackdown on organized crime in Chongqing, opponents were imprisoned, tortured and executed, or lost their jobs and assets without due process of law. But they also believe that those who brought him down may be even more corrupt or despicable.

A lengthy prison term might turn Mr. Bo from a grasping regional politician into a national symbol, or even a martyr. At a time of rampant corruption and social injustice, many see him as a charismatic leftist who at least dared to challenge the status quo of organized crime and official self-dealing and to revive Mao’s socialist, egalitarian ideals. The appearance of pro-Bo images alongside Mao portraits at anti-Japan nationalist demonstrations last September and the arrest on Monday of a Chinese reporter who had urged people to protest the forthcoming trial are signs of this mood.