Seventeenth Amendment to the United States Constitution in 1907, when admitted, and once in 1908. In 1912, Oklahoma reelected Robert Owen by advisory popular vote. Oregon held primaries in 1908 in which the parties would run candidates for that position, and the state legislature pledged to choose the winner as the new Senator. New Mexico, admitted to statehood in 1912, chose only its first two Senators legislatively. Arizona, admitted to statehood in 1912, chose its first two Senators by advisory popular vote. Alaska, and Hawaii, admitted to statehood in 1959, have never chosen a U.S. Senator legislatively. The first direct elections to the Senate following the Seventeenth
Referendums related to the European Union Union. Austria, Sweden, and Finland were admitted as members of the EU, acceding on 1 January 1995. Two countries held referendums on the ratification of the treaty of Amsterdam. The 2004 enlargement of the European Union involved ten candidate states, eight from Central and Eastern Europe, and the Mediterranean islands of Malta and Cyprus. In 2003, referendums on joining the EU were held in all these nations except Cyprus. Since the results were in favourable in all cases, all ten candidate countries were admitted as members of the EU, acceding on 1 May 2004. Denmark and the United Kingdom received