Sheen recorded an ad for the group Catholics for Working Families, which will air on religious radio stations targeting Sens. Arlen Specter (D-Pa.), Mary Landrieu (D-Ark.), and Lisa Murkowski (R-Ak.).
"A bill in Congress called the Employee Free Choice Act will provide a fair and democratic process for workers to form unions," Sheen says in the spot. "And that will help build a more just economy."
"An economy that promotes families, an economy that values human life and serves everyone, not just the people at the top," Sheen continues. "We need laws that protect all workers, especially the most vulnerable: the people who prepare our food, the people who care for our children, the people who build our homes."
Sheen has been in the forefront of celebrity efforts to pass EFCA, having been a longtime union and Catholic activist.
Most notably, Sheen has played Catholic President Jed Bartlet in "The West Wing," and social justice activist Peter Maurin in a biopic of Catholic Worker founder Dorothy Day.
Listen to the ads here.