Until 1913 and passage of the Seventeenth Amendment to the United States Constitution, U.S. Senators were elected by state legislatures, not directly by the people. Progressive Era reformers urged this revision in answer to the corruption of state "machines" under the dominance of party bosses. They also believed that direct elections would make the Senate more responsive to popular concerns regarding the concentrations of business, capital, and labor that in the industrial era gave rise to a growing sense of individual voicelessness. Popular control over the higher affairs of government was...