On April 8, 1913, the direct election of United States Senators was authorized by ratification of the 17th Amendment to the Constitution. Previously, the Constitution required election of Senators by state legislatures. The election of Senators by legislatures was a compromise between the drafters of the Constitution, known as the Connecticut Compromise. The House would be directly elected by the people and representatives would be apportioned by population of each state. The Senate, which would represent states equally with two Senators from each state, would be elected through a more deliberative process in state legislatures.
However, by the late 19th Century, the process for electing Senators had bogged down in some state legislatures. The rise of the Progrerssive movement also pushed for direct election of Senators. With calls for a Constitutional Convention to make changes to the Constitution, in 1912 Congress finally agreed on a joint resolution for the proposed amendment for direct election. The amendment was sent to state legislatures and ratified a year later.