• Sam Rosenfeld

    Assistant Professor of Political Science

    Colgate University

  • Biography

    Welcome! I am an Assistant Professor of Political Science at Colgate University. I have a PhD in History from Harvard University and study political parties and American political development. My research interests include the history of political parties, the intersection of social movements and formal politics, and the politics of social and economic policymaking. My book, The Polarizers: Postwar Architects of Our Partisan Era (University of Chicago Press), offers an intellectual and institutional history of party polarization in the postwar United States.


    I have previously taught at Hamilton College and Wesleyan University. Prior to academia, I worked as a writer and editor at The American Prospect magazine in Washington, DC, where I continue to contribute articles. I hold a BA in History from Columbia University and an MA in History from Harvard.

  • The Polarizers

    Postwar Architects of Our Partisan Era

    Even in this most partisan and dysfunctional of eras, we can all agree on one thing: Washington is broken. Politicians take increasingly inflexible and extreme positions, leading to gridlock, partisan warfare, and the sense that our seats of government are nothing but cesspools of rancor, childishness, and paralysis. The shocking reality, though, is that modern polarization was a deliberate project carried out by Democratic and Republican activists.


    In The Polarizers, Sam Rosenfeld details why bipartisanship was seen as a problem in the postwar period and how polarization was cast as the solution. Republicans and Democrats feared that they were becoming too similar, and that a mushy consensus imperiled their agendas and even American democracy itself. Thus began a deliberate move to match ideology with party label—with the vexed results we now endure. Rosenfeld reveals the specific politicians, intellectuals, and operatives who worked together to heighten partisan discord, showing that our system today is a product not solely of gradual structural shifts but of deliberate actions motivated by explicit agendas. Rosenfeld makes clear that the story of Washington’s transformation is driven both by institutional change and by grassroots influences on the left and the right.


    The Polarizers brilliantly challenges and overturns our conventional narrative about partisanship, but perhaps most importantly, it points us toward a new consensus: if we deliberately created today’s dysfunctional environment, we can deliberately change it.

  • Review quotes

    Matthew Yglesias, cofounder and senior correspondent, Vox

    “Partisan and ideological polarization are defining features of our time, but they are more often denounced than understood. In The Polarizers, Rosenfeld sheds much-needed light on the origins of present-day politics—revealing the human actors who took deliberate steps to bring about the political alignment we know today. His readable, deeply informed narrative should change the way we think about the recent past and even our own times, showing the era of polarization to be not a fall from grace but a plausible response to the very real problems and dilemmas of the old political order. Rosenfeld’s new research and new insights brilliantly challenge much over-crusted conventional wisdom about polarization, and offers hints as to how conscious political action can help redress the flaws of the current party system much as past actors took steps to cure the ills of the past.”


    Andrew Hartman, author of A War for the Soul of America: A History of the Culture Wars

    “Using impressive, indeed herculean, amounts of archival work, Rosenfeld shows that as more and more Americans became politically aware and as, in the wake of the polarizing 1960s, people found ideological cohesion around economic and cultural issues, a growing number of ideologically driven and issue-based activists worked to ensure that the Democratic and Republican Parties respectively represented their cohering interests. Rosenfeld’s analysis is built upon a surprising irony: the very partisanship that so many pundits now lament was something that pundits of an earlier era wanted! The Polarizers is a provocative book that unlocks the black box of partisan polarization.”


    Julian E. Zelizer | author of The Fierce Urgency of Now: Lyndon Johnson, Congress, and the Battle for the Great Society

    “Many observers complain about partisanship in contemporary politics, but Rosenfeld provides a careful and fascinating history of the people who created our current system. Frustrated with the way that bipartisanship had created gridlock in the 1950 and 1960s, partisan entrepreneurs such as Paul Butler believed that strong and ideologically cohesive parties would offer a better way to govern. They believed that partisanship promised to make a stronger democracy. Through tremendous archival research, Rosenfeld shows how this all happened and provides a fresh perspective on the roots of our current system.”


    Ira Katznelson, author of Fear Itself: The New Deal and the Origins of Our Time

    “Less an elegy than an illuminating genealogy, The Polarizers places today’s sharp partisanship in historical context. Moving fluidly between fascinating particulars and systematic analysis, the book’s rich account of persons, motivations, and mechanisms illuminates central transformations within American political life, all the while offering acute judgments about the party system, past and present.”


    Kirkus Reviews

    "A delight for policy wonks and politicos, Rosenfeld's insightful study of the development of political parties since World War II is highly instructive for our current moment."

  • Publications and Media

    Peer reviewed publications

    Works in progress

    The Hollow Parties” (working paper with Daniel Schlozman).


    “A Mix of Motives: The Georgia Delegation Challenge to the 1968 Democratic Convention and the Dynamics of Intraparty Conflict” (working paper with Nancy Schwartz).


    “The Declinist Era in Party Scholarship: An Intellectual History” (working paper).


    “Party Architects: Liberal Origins of Modern Party Polarization” (working paper).

    Selected other publications

    "There's No Going Back," review of The Great Exception by Jefferson Cowie, Democracy: A Journal of Ideas (Spring 2016).


    "Should Liberals Back Public Employee Unions?," review of Government Against Itself by Daniel DiSalvo and Bring Back the Bureaucrats by John J. DiIulio, Jr. The American Prospect (Summer 2015). With Jake Rosenfeld.


    Smooth Operator,” review of The Whole Damn Deal by Kathryn McGarr. The American Prospect (September 2011).


    A Long-Distance Runner,” review of Citizen Rauh by Michael E. Parrish. The American Prospect (December 2010).


    Frustrated by His Own Party,” review of Roosevelt's Purge by Susan Dunn. The American Prospect (November 2010).


    The Way of the Hammer,” feature article on the uses of congressional partisanship. The American Prospect (November 2006).


    The Truth About the Senate,” review of The Most Exclusive Club by Lewis Gould. The American Prospect (December 2005).


    Disorder in the Court,” feature article on liberal and conservative critiques of judicial review. The American Prospect (July 2005).


    Recent media appearances and mentions

    Alan Greenblatt, "Future of the Democratic Party," CQ Researcher, October 13, 2017


    Alan Greenblatt, "Are Democrats Headed for a McGovern Redux?," Politico, October 9, 2017


    Lee Drutman, "The Real Civil War in the Democratic Party," New York Times, July 26, 2017


    Interviews on CTV News, July 21, 2016 and November 9, 2016.


    Maurice Isserman, "How to Make the Democratic Party Platform Actually Matter," In These Times, July 15, 2016.


    E.J. Dionne, "Fighting nostalgia and amnesia in America's search for lost greatness," Washington Post, July 6, 2016.


    Alan Greenblatt, "The Freedom Caucus' Unprecedented Insurgency," Politico, October 18, 2015.


    Matthew Yglesias, "American democracy is doomed," Vox, October 8, 2015.


  • Teaching

    Courses taught

    American Elections and Party Power, Colgate University, Fall 2017 - Syllabus

    The Presidency and Executive Leadership, Colgate University, Fall 2017 - Syllabus

    Topics in Public Policy: College Financing, Hamilton College, Spring 2017 - Syllabus

    Senior Project Seminar: The American Welfare State, Hamilton College, Spring 2015 and Spring 2017 - Syllabus

    American Political Development, Wesleyan University, Spring 2015, Hamilton College, Fall 2016 - Syllabus

    Political Parties and Elections, Hamilton College, Fall 2014, Fall 2016 - Syllabus

    American Political Parties, Wesleyan University, Fall 2015

    American Government and Politics, Wesleyan University, Fall 2015 and Spring 2016

    The American Political Process, Hamilton College, Fall and Spring 2014 - Syllabus

  • Contact

    Sam Rosenfeld

    Assistant Professor, Department of Political Science

    Colgate University

    13 Oak Drive

    Hamilton, NY 13346




    cell: 202-487-9103

    work: 315-228-6464