How did the process for becoming a member of the U.S. Senate change in the 20th century?

In the 20th century, the process for becoming a member of the U.S. Senate changed significantly with the adoption of the 17th Amendment in 1913, which established the direct election of senators by the voters of each state. Prior to this amendment, senators were chosen by state legislatures, which often led to political maneuvering and corruption. The shift to direct election aimed to increase democratic representation and accountability, allowing citizens to have a more direct voice in their government. This change reflected broader reforms in the U.S. political system during the Progressive Era, emphasizing transparency and public participation.