The appointment of senators by the state legislatures . . . is recommended by the double advantage of favoring a select appointment, and of giving to the state governments such an agency in the formation of the federal government, as must secure the authority of the former.
James MadisonThe public affairs of the union are spread throughout a very extensive region, and are extremely diversified by the local affairs connected with them, and can with difficulty be learnt in any other place, than in the central councils, to which a knowledge of them will be brought by the representatives of every part of the empire. Yet some knowledge of the affairs, and even of the laws of all the states, ought to be possessed by the members from each of the states.
James Madison