In 1995 Obama openly sought and obtained the endorsement of the Marxist New Party in his quest to be elected to the Illinois State Senate.
June 3, 2008
Obama's Alliance with Marxists
http://www.americanthinker.com/blog/..._marxists.html
Also well supported and referenced in two great books:
Dreams from My Father, by BHO
and
The Roots of Obama's Rage by Dinesh D'Souza