A peer-reviewed study published in the March 2025 edition of the journal Political Behavior provides a rigorous examination of long-term trends in American political behavior. The analysis, written by political scientists Dr. John Sides of Vanderbilt University and Dr. Michael Tesler of the University of California, Irvine, in collaboration with researchers at the Pew Research Center, draws on two of the most authoritative long-running datasets in political science: the American National Election Studies (ANES) and the General Social Survey (GSS).
By relying on data collected by the ANES since 1948 and the GSS since 1972, the study establishes a deep historical baseline for measuring shifts in public opinion and partisan alignment across decades rather than within a single election cycle. Dr. Sides, who previously served on the faculty at the University of Maryland, is the co-author of the 2018 book Identity Crisis: The 2016 Presidential Campaign and the Battle for the Meaning of America, which examined the forces reshaping Republican and Democratic coalitions.
Dr. Tesler’s research centers on how racial and partisan identities influence political attitudes, a perspective increasingly central to understanding the American electorate. The Pew Research Center, a nonpartisan think tank founded in 1990 and based in Washington, D.C., contributes its own institutional expertise in public opinion polling and demographic research.
The findings have undergone peer review, adding to the academic literature on voter behavior.
Decades of Survey Data as a Foundation
The study’s reliance on the ANES and GSS provides a uniquely long view of electoral dynamics. The American National Election Studies have surveyed voters every election cycle since 1948, while the General Social Survey, fielded by NORC at the University of Chicago, has operated continuously since 1972. Together, these datasets allow researchers to track how the electorate has evolved over more than seven decades. This historical perspective is critical for distinguishing temporary electoral shifts from deeper, structural changes in partisan attachments and public opinion.
The research signals to analysts that identity and group membership are becoming increasingly central drivers of political choice, often outweighing purely policy-based or economic calculations.
Implications for a Polarized Electorate
The broader stakes of this research lie in its implications for how campaigns, political parties, and the media understand a deeply polarized electorate. The study describes a political landscape where partisan identities are hardening and cross-cutting cleavages are weakening. These domestic fault lines have direct consequences for American governance and foreign policy.
A political system characterized by durable partisan attachments affects the country’s capacity for stable governance and coherent policy on the world stage. As the 2026 midterm elections approach, the data from Sides, Tesler, and the Pew researchers will serve as a key reference point for strategists seeking to navigate an environment defined by deep and lasting partisan divisions.
The study does not offer prescriptions, but it provides an empirical map of the terrain.
Historical Context of American Political Behavior
The United States emerged from a colonial struggle that began with European discovery of the Americas in 1492 and British settlement at Virginia in 1607. Enlightenment ideals of republicanism and liberalism spread through the Thirteen Colonies, fueling a revolution against British rule. Independence was declared in 1776, and victory in the Revolutionary War secured international recognition. The nation then expanded westward, acquiring territory through purchase, settlement, and conquest.
A deep divide over slavery led eleven Southern states to secede, triggering the Civil War from 1861 to 1865. The Union’s victory preserved the country and abolished slavery nationally.
By the early twentieth century, the United States had become a great power, a status confirmed by its involvement in World War I. After Japan’s attack on Pearl Harbor in 1941, the U.S. entered World War II alongside the Allies. The war’s end left the United States and the Soviet Union as rival superpowers competing for global influence throughout the Cold War.
The collapse of the Soviet Union in 1991 left the United States as the world’s sole superpower. Today, the United States is a federal republic composed of fifty states and a federal capital district.
It occupies a large portion of North America, bordered by Canada to the north and Mexico to the south, with Alaska in the northwest and Hawaii in the Pacific. The country also holds several island territories. Its population is large and diverse, shaped by centuries of immigration.
The federal system divides power between a national government and state governments, with elections serving as the primary mechanism for political representation. Understanding American political behavior has long been a central concern for scholars, and the long-term data from the ANES and GSS provide essential context for how the electorate evolves and why those shifts matter for governance in an era of intense polarization and shifting party coalitions.
