In the U.S. Constitutional Convention, Governeur Morris said on July 2, 1787, that the “Rich will strive to establish their dominion & enslave the rest. They always did. They always will. The proper security [against] them is to form them into a separate interest.” By this he meant the U.S. Senate. The democratic principle in the U.S. House and the aristocratic spirit in the U.S. Senate “will then controul each other.” (Madison, p. 233) Having the State Legislatures appoint their U.S. Senators—as was the case until 1913—would defeat the independence of the Senate, and hence its function as a check on the excesses of democracy in the U.S. House. Such excesses had just been evinced in Shays’ Rebellion in Massachusetts, wherein the legislature there had sided with the former soldiers who had not been paid for their service but were still to make payments on their debts. In other words, one of the purposes of the U.S. Senate as originally envisioned was to protect property (including creditor interests).
The full essay is at "The U.S. Senate as Protector of the Rich."
