John Haines, whose death was recently announced over on GT, wrote a number of political poems--including a satirical series called "Diogenes in Washington" which I can't find in my books.
I found this late poem of his,
"Notes on the Capitalist Persuasion", online.
He was a good friend of Hayden Carruth and Wendell Berry, two other poets who were/are outspoken about politics in their poetry.
(Editing back in to add that I don't think this is a particularly memorable poem, and in fact is a good example of some of the pitfalls of writing political poetry. So I guess it only fits half the description of this thread--it's political but not kickass. John H.
did write some kickass political stuff as well, but I don't have time to find it or type it in at the moment.)