Answer:
Mao simply told the peasantry that he felt they were important and that the rich were treating them as less than human. He promised them social status and promised to bring the rich down. In many ways he was not lying, the peasantry were treated very poorly by the rich and powerful in China. Mao did intend to bring the rich down and elevate peasants.
It was not at all difficult to gain popular support. Of course those supporters could not see what the future would bring in just a decade.
