The 17th Amendment to the United States Constitution, ratified in 1913, established the direct election of Senators by the people. Each state has two Senators who were originally chosen by the state legislatures. After the Civil War, an increasing number of issues involving bribery and corruption in the selection of Senators led to a movement in favor of direct election.
In addition to cases of bribery and corruption, many states found it difficult to choose Senators, often leading to lengthy periods when a Senate seat remained vacant. Delaware was unable to choose a Senator for four years at one point, leaving the seat vacant from 1899 to 1903. A number of states began experimenting with different methods of electing Senators, including direct elections or statewide referendums.
Senator Joseph Bristow of Kansas introduced an amendment in 1911 to establish the direct election of Senators. While the amendment met some opposition, it passed the Senate and moved to the House of Representatives. After a great deal of debate, the House passed the amendment in May 1912 and sent it to the states. Massachusetts ratified the amendment almost immediately, and by April 1913, three-quarters of the states had ratified it. At the end of May 1913, it became part of the Constitution.