Most members of Congress begin their careers through regularly scheduled elections, but terms may be cut short due to death, scandal, or different career opportunities. In these cases, special elections are held to fill vacancies. This book is the first large-scale scholarly treatment of special elections: both in terms of explaining what factors influence outcomes and in determining whether special elections are bellwethers for general elections. Based on 75 years of data, Charles S. Bullock, III and Karen L. Owen closely examine several competitive special elections during the first two years of the Trump era and quantitatively assess the almost 300 House special elections held since World War II.