Seth Masket is Professor of Political Science and Director of the Center on American Politics at the University of Denver. Masket writes regularly for Mischiefs of Faction and FiveThirtyEight. His work has also appeared in Politico, the New York Times, the Los Angeles Times, and the Washington Post's Monkey Cage. He is the author of The Inevitable Party: Why Attempts to Kill the Party System Fail and How They Weaken Democracy (2016) and No Middle Ground: How Informal Party Organizations Control Nominations and Polarize Legislatures (2009).