To answer this question, among others, I analyzed data from surveys and interviews with professors, including a nationally-representative survey of the American professoriate, conducted in 2006 with the sociologist Solon Simmons. My research shows that only about 9 percent of professors are political radicals on the far left, on the basis of their opinions about a wide range of social and political matters, and their self-descriptions (for example, whether they describe themselves as radicals). More common in the professoriate—a left-leaning occupation, to be sure—are progressives, who account for roughly a third of the faculty (and whose redistributionism is more limited in scope), and academics in the center left, who make up an additional 14 percent of professors.
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But who are academic radicals, and what do they believe? This is a diverse category, encompassing social democrats, radical feminists, radical environmentalists, the occasional postmodernist—and yes, some Marxists. All told, about 43 percent of radical professors say that the term “Marxist” describes them at least somewhat well. (About 5 percent of American professors, over all, consider themselves Marxists.)