I'll tell you what the difference between the CPC and KMT mindset is, which determined each of their fate.
CPC places emphasis on self-reliance and mobilizing the working class for its goals. It is also good at picking the right people for the right job, and developing talents from the bottom. While this hasn't always been consistent, it has been the general pattern. There is a deviation from this in recent years due to corruption, but that's another subject on its own.
The KMT, on the other hand, runs around begging for foreign help the moment trouble hits. It relied on an oligarchy of wealthy families and powerful warlords to maintain its rule, therefore disconnected from the peasants, workers and even middle class. The lack of backbone is apparent by the fact that it didn't have the guts to declare war on Japan until 1941 after the Americans had done so, despite the fact that Japan already launched a full invasion in 1937. Its leadership were notoriously incompetent and corrupt, botching the war effort and losing the entire country to communists within a decade. Even this day, they're still serving as America's pawn against China despite claiming to be the "legitimate" government of China.