December 17, 1918, and McNary was then reappointed to the Senate on December 12, 1918, and took office on December 18, instead of taking office in January, when his term he was elected to would have started. Mulkey resigned in order to give McNary a slight seniority edge over other new members of the Senate. In 1920, former adversary Stanfield defeated incumbent Democrat George Earle Chamberlain for Oregon's other Senate seat, making McNary the state's senior senator. McNary won re-election four times, in 1924, 1930, 1936, and 1942, serving in Washington, D.C., until his death. Senate years After World War I, Wilson sought Senate approval of the Treaty of Versailles. Because the treaty included provisions for establishing and joining the League of Nations, one of Wilson's Fourteen Points, Republicans opposed it. Going against much of his party, McNary, part of a group of senators known as "reservationists", proposed minor changes to support the United States entry into the League. Ultimately, the Senate never ratified the Treaty of Versailles, and the United States never joined the League. One of the prime opponents of Wilson and the League was Senate Majority Leader Henry Cabot Lodge. After McNary demonstrated his skill in the debate over the League, Lodge took him under his wing, and the two formed a longtime friendship. The friendship helped McNary secure favorable committee assignments and ushered him into the inner power circle of the Senate. Early in his career, he served as chairman of the Irrigation and Reclamation of Arid Lands Committee, and as a member of the Agriculture and Forestry Committee. In 1922, President Warren G. Harding asked McNary to be the Secretary of the Interior to replace Albert B. Fall because of Fall's involvement in the ongoing Teapot Dome scandal. McNary declined, preferring to stay in the Senate. In 1933, McNary was selected as the Senate Minority Leader by fellow Republicans, while the Senate was under Democratic control during the New Deal era. He remained Minority Leader for the rest of his time in office and "hovered most of the time on the periphery of the Republican left" and opposed disciplining Republican senators who supported Roosevelt. He supported many of the New Deal programs, at the beginning of Roosevelt's presidency. As World War II approached, he favored "all aid to England and France short of war". He voted to keep an arms embargo in place but supported