Obama is not a “Marxist.” To call him one shows your ignorance. He is a socialist, yes, but there is no indication that he adheres to Marxian or even “vulgar” Marxian thought.
Read Thomas Sowell’s book on Marx for the best explanation of Marx you will ever read.
We make ourselves look stupid when we mislabel people. Just call him a socialist. Use real arguments, not epithets.
I believe he is closer to Anarcho-syndicalism
“From each according to his ability, to each according to his need.”
It’s not like Baraq Hussein Ubama has ever uttered such redistributive rhetoric.