A founding editor of Socialist Revolution (now Socialist Review) in 1969, and of East Bay Voice in the 1970s, Judis started reporting from Washington in 1982, when he became Washington correspondent for In These Times. He has also written for GQ, Foreign Affairs, Mother Jones, The New York Times Magazine, and The Washington Post.

In 2002, he published a book (co-written with political scientist Ruy Teixeira) arguing that Democrats would retake control of American politics, thanks in part to growing support from minorities and well-educated professionals. The title, The Emerging Democratic Majority, was a deliberate echo of Kevin Phillips' 1969 classic, The Emerging Republican Majority. The book was named one of the year's best by The Economist magazine.

In 2002, he published a book (co-written with political scientist Ruy Teixeira) arguing that Democrats would retake control of American politics, thanks in part to growing support from minorities and well-educated professionals. The title, The Emerging Democratic Majority, was a deliberate echo of Kevin Phillips' 1969 classic, The Emerging Republican Majority. The book was named one of the year's best by The Economist magazine.