The 17th amendment to the US Constitution ended representation of the sovereign states in the federation they had formed. US Senators had been selected by the governments of the several states and they served at the pleasure of the state governments they represented. The Senate was to be the protector of the rights of the people that were vested in their states. The amendment made the US Senate a second house of representatives elected by popular vote, which moved the United States from a classic democratic republic to a position much closer to a democracy.