With so many Americans turning away from religion, it's natural to wonder whether a Secular Left can ever challenge the Religious Right. A new book attempts to answer that question. It's called "Secular Surge: A New Fault Line in American Politics," and it's written by three people who know this topic better than most people ever could.

David E. Campbell is the Packey J. Dee Professor of American Democracy at the University of Notre Dame who has written extensively about religion's role in American politics.

Geoffrey C. Layman is Professor of Political Science at the University of Notre Dame. He, too, has written a lot about religion and politics and is currently the co-editor of the journal Political Behavior.

David and Geoffrey are joining me today.

The third author is John C. Green, the Emeritus Director of the Bliss Institute of Applied Politics at the University of Akron.

We talked about whether the "secular surge" has peaked, if the GOP can appeal to non-religious voters, and the single issue that could unite atheists and evangelicals.