U'Ren associated himself with many initiative efforts, including banning free railroad passes, establishing popular election of U.S. Senators, and creating the first presidential primary in the United States. Two of the more significant early initiatives he sponsored were a 1906 constitutional amendment extending initiative and referendum powers to local jurisdictions, and a 1908 amendment that gave voters power to recall elected officials. In 1912, he proposed an amendment to the Oregon Constitution to essentially weigh each legislator's vote on proposed bills according to the number of votes he received in the last election; this measure failed by a large margin.