In the movie "Gladiator" the people of Rome, with the exception of the lavish, rich Patrician, were thought of as a "mob" of unruly people whose lives are entirely dependent on the emperor. At the very beginning, Marcus Aurelius makes reference to the massive difference in social class in Rome, pointing out how there is rich, there is poor, but there is little in between.
Lucilla goes as far as saying that Maximus does not have enough in him to keep such mob under control. That Rome is so unruly and feral that it takes an emperor willing to use any tactic to keep them in shape. In Lucilla's words, the megalomaniac tendency of Commodus to make people depend on him for life, food, entertainment, mercy, and discipline is perhaps all that could possibly keep Rome from imploding.
That is power, the mob is Rome. And while Commodus controls them he controls everything
Maximus also saw Rome as a mob. He knew what the weak tastes of the people were. However, rather than wanting to rule them from the top down, he wished to see a liberated mob that would redefine itself and will allow itself to be ruled properly. The fact that, in the movie, the people of Rome resonated with Maximus more so than with Commodus gives us an idea that, as people, they were more powerful than they thought but were also very much disenfranchised. In not so many words, the people were the handlers of the power, without them even know it it. They had given all of their power to the emperor.