George David Aiken (August 20, 1892 – November 19, 1984) was an American politician and horticulturist. A member of the Republican Party, he was the 64th governor of Vermont (1937–1941) before serving in the United States Senate for 34 years, from 1941 to 1975. At the time of his retirement, he was the most senior member of the Senate, a feat which would be repeated by his immediate successor Patrick Leahy.

As governor, Aiken battled the New Deal over its programs for hydroelectric power and flood control in Vermont. As a Northeastern Republican in the Senate, he was one of four Republican cosponsors of the Full Employment Act of 1946. Aiken sponsored the food allotment bill of 1945, which was a forerunner of the food stamp program. He promoted federal aid to education and sought to establish a minimum wage of 65 cents in 1947. Aiken was an isolationist in 1941 but supported the Truman Doctrine in 1947 and the Marshall Plan in 1948.

In the 1960s and 1970s, he steered a middle course on the Vietnam War, opposing Lyndon Johnson's escalation and supporting Richard Nixon's slow withdrawal policies. Aiken was a strong supporter of the small farmer. As acting chairman of the Senate Agriculture Committee in 1947, he opposed high rigid price supports. He had to compromise, however, and the Hope-Aiken Act of 1948 introduced a sliding scale of price supports. In 1950, Aiken was one of seven Republican senators who denounced in writing the tactics of Senator Joseph McCarthy, warning against those who sought "victory through the selfish political exploitation of fear, bigotry, ignorance and intolerance."

George David Aiken was born in Dummerston, Vermont, to Edward Webster and Myra (née Cook) Aiken. In 1893, he and his parents moved to Putney, where his parents grew fruits and vegetables and his father served in local offices including school board member, select board member, and member of the Vermont House of Representatives. Aiken received his early education in the public schools of Putney, and graduated from Brattleboro High School in 1909. Aiken developed a strong interest in agriculture at an early age, and became a member of the Putney branch of the Grange in 1906. In 1912, he borrowed $100 to plant a patch of raspberries; within five years, his plantings grew to five hundred acres and included a nursery. From 1913 to 1917, Aiken grew small fruits in Putney with George M. Darrow as "Darrow & Aiken." In 1926, Aiken became engaged in the commercial cultivation of wildflowers. He published Pioneering With Wildflowers in 1933 and Pioneering With Fruits and Berries in 1936. He also served as president of the Vermont Horticultural Society (1917–1918) and of the Windham County Farm Bureau (1935–1936).

In 1914, Aiken married Beatrice Howard, to whom he remained married until her death in 1966. The couple had three daughters, Dorothy Howard, Marjorie Evelyn (who married Harry Cleverly), and Barbara Marion; and one son, Howard Russell. In 1967 Aiken married his longtime administrative assistant, Lola Pierotti. Lola Aiken remained active in Republican politics until her death in 2014 at age 102.

Aiken served as a school board member in Putney from 1920 to 1937. A Republican, he unsuccessfully ran for the Vermont House of Representatives in 1922. In 1930, he ran successfully. He was reelected in 1932 and served from 1931 to 1935. As a state representative, he became known for his opposition to private power companies over the issue of dam construction. Aiken was elected as Speaker of the House in 1933, over the opposition of the Republican establishment. As Speaker, he shepherded the passage of the Poor Debtor Law, which protected people who could not pay their obligations during the Great Depression.

In 1934, Aiken won election as Lieutenant Governor of Vermont. During his 1935 to 1937 term, Democrats had achieved more representation in the Vermont Senate than they had previously, though with only seven senators as compared to 23 Republicans, they were still heavily in the minority. Aiken used his position on the senate's Committee on Committees — the lieutenant governor, President pro tempore of the Vermont Senate, and a senator elected by the rest of the body — to ensure that Democrats were fairly represented on the senate's committees. As a result of Aiken's initiative, Democrats were represented on almost every committee, and constituted a majority on two. In addition, Aiken ensured that Elsie C. Smith, the state senate's only female member, was fairly considered with respect to committee assignments; in fact, Senator Smith was appointed to more committees than any of her peers.

In 1936, Aiken won election as governor, serving from 1937 to 1941. Aiken earned a reputation as a moderate to liberal Republican, supporting many aspects of the New Deal, but opposing its flood control and land policies. In his second term the governor launched attacks on electric utility companies, and sponsored a bill that made the Public Service Commission independent of the utilities for technical advice. To continue the effort to form a consumer-oriented PSC, he named the former head of the Vermont Farm Bureau as its chairman.