3. Bill Clinton – 46 years, 154 days at Start of presidency
William “Bill” Clinton (born August 19, 1946) is an American politician who served as the 42nd president of the United States from 1993 to 2001. Prior to the presidency, he was the governor of Arkansas from 1979 to 1981, and again from 1983 to 1992, and the attorney general of Arkansas from 1977 to 1979. A member of the Democratic Party, Clinton was ideologically a New Democrat, and many of his policies reflected a centrist “Third Way” political philosophy.
2. John F. Kennedy – 43 years, 236 days at Start of presidency
John F. Kennedy (May 29, 1917 – November 22, 1963), commonly referred to by his initials JFK, was an American politician and journalist who served as the 35th president of the United States from January 1961 until his assassination in November 1963. He served at the height of the Cold War, and the majority of his presidency dealt with managing relations with the Soviet Union. A member of the Democratic Party, Kennedy represented Massachusetts in the U.S. House of Representatives and Senate prior to becoming president.
1. Theodore Roosevelt – 42 years, 322 days at Start of presidency
Theodore Roosevelt Jr. (October 27, 1858 – January 6, 1919) was an American statesman, politician, conservationist, naturalist, and writer who served as the 26th president of the United Statesfrom 1901 to 1909. He previously served as the 25th vice president of the United States from March to September 1901 and as the 33rd governor of New York from 1899 to 1900. As a leader of the Republican Party during this time, he became a driving force for the Progressive Era in the United States in the early 20th century. His face is depicted on Mount Rushmore, alongside those of George Washington, Thomas Jefferson, and Abraham Lincoln.