David Mayhew’s 1974 thesis on the “electoral connection” and its impact on legislative behavior is the theoretical foundation for research on the modern U.S. Congress. Mayhew contends that once in office, legislators pursue the actions that put them in the best position for reelection. The electoral connection is a post-World War II phenomenon, but legislative scholars now suggest that Mayhew’s argument applies to earlier congressional eras. To assess these claims, Carson and Sievert investigate whether earlier legislators were motivated by the same factors that influence their behavior today, especially in pursuit of reelection. They examine how electoral incentives shape legislative behavior throughout the nineteenth century by looking at patterns of turnover in Congress; the re-nomination of candidates; the roles of parties in recruiting candidates, and by extension their broader effects on candidate competition; and, finally by examining legislators’ accountability. The results have wide-ranging implications for the evolution of Congress and the development of various legislative institutions over time.