Collaborative Research: Primary Elections for U.S. State and Federal Offices: A Comprehensive Database and Analysis


Shigeo Hirano
Professor of Political Science


The emergence of the primary election process during the 20th Century is widely thought to have transformed American politics. For example, primary elections allegedly weakened political parties and fueled the rise of personalistic, incumbency oriented politics; and primary elections are though to have made politicians much more ideologically extreme than the electorate as a whole, because candidates must first win approval of a partisan subset of the electorate before they can even qualify for the general election.
Addressing even the most basic questions about this two-stage process is difficult because no comprehensive database on primary election results in the U.S. currently exists. This project assembles a database on primary elections for statewide and federal offices. For each state, we collect election returns for every statewide and federal office for major-party primary elections from the year the first primaries were held to the present.
Our project yields broad educational and social benefits including useful digital databases archived at the ICPSR and on our own websites, publications in a variety of media, data sets made available to state election boards and/or secretaries of state, research collaboration between three major educational institutions, mentoring and employing research assistants who are women and under-represented minorities, and professionalization of undergraduates and graduate students who co-author with the principal investigators.