The soldiers can't be everywhere. A coordinated protest in many rural districts would work. During the long, long history of China, peasant revolts frequently brought down regimes.
I'm not convinced that the general run of the mill Chinese silent majority is interested in such a thing. Yes, there will be the occassional disturbance. Heck, there are here too at times. I still believe the government holds the cards.
Yes, you're probably right about peasant revolts. I still maintain it doesn't take many bodies to convince folks that the odds aren't in their favor.