Haymarket Books, the book publishing arm of Chicago’s progressive Center for Economic Research and Social Change, has enjoyed a 43% spike in sales this year, driven by a hot title and the Occupy movement.

Its top-seller is The John Carlos Story: The Sports Moment That Changed the World by John Carlos with Dave Zirin. Released last September, The John Carlos Story is the memoir of one of the athletes who gave a Black Power salute while standing at the podium at the 1968 Olympic Games; it has sold 13,321 copies to date in hardcover, with 4,322 copies selling after a photograph of Nelson Mandela reading it was widely circulated in January.

It wasn’t only the photograph of Mandela reading Carlos that gave the book a push, explained Haymarket Books publicity director Sarah Macaraeg. Carlos and Zirin embarked last fall on an author tour to college campuses around the country that “turned into an Occupy tour” after Carlos started visiting Occupy camps in such cities as New York City, Chicago, and Washington, D.C., drawing huge crowds.

Macaraeg noted that the Occupy movement in general has raised Haymarket’s profile, as the press has connected Occupy organizers with other authors whose works, the press thinks, will resonate with those involved in that political movement. The press has also donated hurt titles to Occupy libraries across the country.

The Occupy movement led Haymarket to publish Occupying Wall Street, a drop-in title that is a narrative of the movement’s history; it was released in March with a 4,000-copy initial print run. In addition, Haymarket has begun publishing political pamphlets, priced at $4.95, that are being marketed to Occupy activists. “Occupy is our moment,” Macaraeg said. “It’s everything we’ve been publishing toward.” Haymarket’s list includes titles from such well-known left thinkers as Noam Chomsky and Amy Goodman, whose third title from Haymarket, The Silenced Majority, will be released in August.

Revenues are expected to continue to grow, as the press aggressively expands into other categories beyond the political titles it’s been publishing since its debut release, Struggle for Palestine, edited by Lance Selfa, was published in 2002. In September 2011, Haymarket released its first poetry collection, L-vis Lives by Chicago poet Kevin Coval, which has sold 6,000 copies to date. This spring, Haymarket published its first literary fiction title, Is Just a Movie by Earl Lovelace, with a 3,000-copy initial print run.

The press’s first four-color illustrated art book, The Black Power Mixtape 1967–1975, edited by Swedish documentary filmmaker Goran Higo Olsson, will be released in August, and Haymarket’s first book of lyrics, which will also be published as an “enhanced e-book” with lyrics, audio, and photos, Boots Riley: Lyrics in Context, 1993–2012 by Boots Riley, of the hip-hop group the Coup, will be published in October. “These [poets and novelists] speak a different language,” Macaraeg noted. “But they have something critical and beautiful to say.”

In 2006, Haymarket entered the YA market with the release of A Little Piece of Ground by Elizabeth Laird. In 2003, when Macmillan Children’s Books had first published this novel about a Palestinian boy living in Ramallah, a firestorm of controversy erupted. The book was effectively banned in Canada and many book reviewers in the U.S. and Canada would not review it. “No one would touch it,” Julie Fain, Haymarket’s managing editor, recalled. “So we published it.” More than 10,000 copies of the Haymarket edition were sold, making it the company’s bestselling YA release. Haymarket has published three more YA novels since then, including Laird’s Red Sky in the Morning, a March 2012 release.

While Haymarket titles are distributed by Consortium, the press emphasizes direct sales to organizers and organizations. The press reports $1.2 million in gross revenues this fiscal year, with book sales generating 60% and the remaining coming from grants and contributions. About 50% of Haymarket’s book sales come from Amazon and bricks-and-mortar retailers; the balance is generated by special sales, sales to individuals, and sales at events. “To us the definition of a successful book is not always commercial success. It has to do with achieving social justice and changing the world,”said Fain.