I am a political scientist at Johns Hopkins University. I study political parties, American political development, social movements, and political history.
I have written two books, both published by Princeton University Press. The Hollow Parties: The Many Pasts and Disordered Present of American Party Politics, written with Sam Rosenfeld at Colgate University, was published in May 2024, and a paperback edition with a new preface appeared in October 2025. Here’s a link to various material about the book.
My first book, When Movements Anchor Parties: Electoral Alignments in American History, was published in 2015. Here’s an interview reflecting on its themes.
I'm working on two more books. With Sam Rosenfeld, I’m writing a short book about the limits of expecting policy solutions to political problems in the contemporary Democratic Party. And on my own, I’m continuing work on a long book about leading sectors in the US economy and party politics since the Gilded Age.
I live in Baltimore, Maryland (buy seafood at Faidley’s) and Chilmark, Massachusetts (buy seafood at Larsen’s).
