His early views on the Khmer Rouge were bonkers.

But Marxist - no.
As I said before, I think you are not too well informed about what Marxism entails, Booner. Of course he is influenced by Marxist thoughts, I would expect him to be familiar with it, that's a common feature of "the Left", specially his economic theories - no way around that, but I don't think he believes in dialectic materialism nor in a united working class revolution, in fact he has been very critical of Leninism - it's not empowering the people but replacing one structure of authority with another.

You'll get a better understanding of this if you look at the early 20th century and the dynamic between communists and anarchists. But that's moving away from Chomsky, just a sidenote...