What specifically do you mean by that and when? The Communist Party USA began shortly after the Bolshevik Revolution in Russia, and geographically had its greatest presence in Chicago and New York. Eventually Communist activity spread to other locations, so I wouldn't be surprised if there was some in Minnesota. Do you know of any well-known early twentieth century American communists from Minnesota? Can't think of any offhand.
Abolitionists were also frequently Utopian dreamers.
Maybe so, but they couldn't be called Marxists because they predated the publication Marx's works.
Stick to things you know about.