Hubert Horatio Humphrey Jr. was an American politician and statesman who served as the 38th vice president of the United States from 1965 to 1969. He twice served in the United States Senate, representing Minnesota from 1949 to 1964 and 1971 to 1978. As a senator he was a major leader of modern liberalism in the United States. As President Lyndon B. Johnson's vice president, he supported the controversial Vietnam War. An intensely divided Democratic Party nominated him in the 1968 presidential election, which he lost to Republican nominee Richard Nixon.

The vice president of the United States (VPOTUS) is the second-highest officer in the executive branch of the U.S. federal government, after the president of the United States, and ranks first in the presidential line of succession. The vice president is also an officer in the legislative branch, as the president of the Senate. In this capacity, the vice president is empowered to preside over the United States Senate, but may not vote except to cast a tie-breaking vote. The vice president is indirectly elected together with the president to a four-year term of office by the people of the United States through the Electoral College. Since the passage of the Twenty-fifth Amendment to the US Constitution, the vice president may also be appointed by the president to fill a vacancy, via majority confirmation by both the Senate and the House.