Federalist No. 62
Federalist No. 62, authored by James Madison under the pen name Publius, is the sixty second of 85 essays. Titled " The Senate", Madison puts a focus on four areas: the qualifications of senators, the appointment of them by the legislatures of the states, the equal representation of states(2 per), and the election terms of senators.
It was published on February 27, 1788.
The structure of the Senate as representatives of the states was changed to direct popular vote in 1913 by the 17th amendment.