With my immense knowledge of this part of the world, ahem, surely the identification with socialism was the best way of posturing themselves against the yankees and tap into that resevoir of distrust and hate of the US in South America; United Fruit a particular in-your-face symbol of that relationship. On the other hand, you also gain an ally in the Soviet Union who, to my knowledge, were very supportive of foreign communist movements during the Cold War. Support, the US wasn't going to give.
I cannot recall many influential indigneous communists although they may be outside of my knowledge. You have your Jose Martis but he was as white as a sheet.
Is Chavez the foremost?
It points to the idea that idealogy wasn't the driving force behind these leaders' convictions but a way of accruing the two benefits i mentioned above.
/mindless speculation over.
Personally I think this way of thinking is more correct than people realize ^. Nearly every revolution/guerrilla movement in the 20th century in Latin America often struggled actually at gaining indigenous support, because guerrilla movements were typically led by white ideologues with little real knowledge of the backcountry where they tried to set up these movements.
IE in Guatemala when the EGP first came to the highlands, it took them nearly half a decade to really garner any substantial indigenous support partly because people didn't initially believe the revolutionaries had their interests at heart and repercussions. The same played out in Nicaragua where the natives around Matagalpa actively helped the government because despite the FSLN's promises of good will - land, goods, and labor were seized and all the indigenous poor got in return was additional risk. Another example in Peru when the Shining Path was first starting out Marxists believed they could use the isolated area of Ayacucho as their base. The Huaychainos who had no love for the Peruvian government, welcomed these new guerrillas into their homes and then butchered them because they threatened the system of communal law and order in the indigenous dominated Ayacucho.
The point is indigenous support in general was lukewarm for marxist ideologies. Typically where support was given, it often waned quickly among indigenous populations when promises like land reform, equality, etc. often did not really apply to them. And its true that indigenous were most of the time the footsoldiers in guerrilla armies, but they were rarely and if ever officers. And the same actually goes for Government armies. IE in Guatemala hundreds of thousands of Maya fought for the government - so many in fact that there were more indigenous fighters for the government than there were for the guerrillas despite government atrocities [Not to say people agreed with the government, but just showing this because people often acted as footsoldiers for these movements because the alternative was retribution - IE a personal example, someone I am related to had his family shot and head cut open by guerillas in Comalapa. Using their blood the guerillas painted a warning to those who didn't support them fully in the village - Many fought on both sides of the civil war in that village, not because of ideological reasons but for survival]. Typically indigenous people didn't really believe in Marxist ideologies and this is shown by the huge apathy numerically towards guerrilla movements, where possible people tried to use the guerrillas for their advantage - Cases like Zapatista's army and the Cruzob revolution go to show that the armies that enjoyed true indigenous support, were fighting for indigenous causes first and second-hand ideologies second.
If institutionally indigenous had been educated across Latin America, many of the Marxist movements still wouldn't have incorporated natives significantly into leadership. IE when Che was fleeing from Guatemala and came in contact with the Cubans preparing for their revolution, he met a Quiche landlord sympathetic to the new status of exile for communists that wanted to accompany them on their guerrilla training, but was too "strategically focused" and willing to "compromise" that eventually he was dismissed before they even set off to Cuba. The "smart native" made Castro uncomfortable - machismo and subconscious racial distrust would have ensured that the power structure of the guerrilla movements would have put Marxist ideas over indigenous ideas and would have been reflected in leadership even if there had been a "qualified" population for leadership.