For Maoist

[Bright Banana Beard]

Why it is the peasant is the most revolutionary?

[The New Manifesto]

Because 90% of China in 1930s was peasant-based and the KMT had securely crushed worker revolts in the Cities. This was part of the Maoist materialist practice of "seeking truth from facts". The idea that Maoism means universally all revolutions need to be rural based is ludicrous.
This

[Dros]

It's not and Maoists don't believe that. Maoism believes that the Vanguard party of the PROLETARIAT and the proletarian communist movement can work with peasants and create a revolution with peasants but guided fundamentally by the interests of the proletariat as a class.

[bezdomni]

The peasantry isn't the most revolutionary class - the proletariat is and nothing can change that. However, when you're talking about China (or even Russia) when the vast majority of the population is peasantry...it's possible and desirable for the proletariat to be the leading force of the revolution, while the peasantry is the main force.

It's not so much the percentage breakdown of peasants in the party vs workers in the party or peasants in the red army vs workers in the red army that will determine how revolutionary the party is or how successful the red army is, it's about having a correct and revolutionary political orientation and the basis in the masses (with whatever class composition there is).