Given the following context:  Hubert Humphrey was a Minnesotan who became a nationally prominent politician. He first ran for mayor of Minneapolis in 1943, but lost the election to the Republican candidate by just a few thousand votes.  As a Democrat, Humphrey recognized that his best chance for political success was to obtain the support of the Minnesota Farmer-Labor Party.  Other members of the Farmer-Labor Party had been considering the idea, as encouraged by Franklin D. Roosevelt, but the merger only became reality after Humphrey traveled to Washington, D.C. to discuss the issue.  Rather than simply absorbing the Farmer-Labor party, with its constituency of 200,000 voters, Humphrey suggested calling the party the Minnesota Democratic-Farmer-Labor Party.  He was elected mayor of Minneapolis in 1945, and one of his first actions was to propose an ordinance making racial discrimination by employers subject to a fine.  This ordinance was adopted in 1947, and although few fines were issued, the city's banks and department stores realized that public relations would improve by hiring blacks in increasing numbers. Humphrey delivered an impassioned speech at the 1948 Democratic National Convention encouraging the party to adopt a civil rights plank in their platform.  He was elected to the United States Senate in 1948 and was re-elected in 1954 and 1960.In the early 1960s, the topic of civil rights was coming to national prominence with sit-ins and marches organized by Martin Luther King Jr. and other black leaders.  In 1963, President John F. Kennedy sent a comprehensive civil rights bill to Congress, based largely on the ideas that Humphrey had been placing before the Senate for the previous fifteen years.  The bill passed the House in early 1964, but passage through the Senate was more difficult, due to southern segregationists who filibustered for 75 days.  Finally, in June 1964, the Civil Rights Act of 1964 became law.  Humphrey called this his greatest achievement. Lyndon B. Johnson recruited Humphrey for his running mate in the 1964...  answer the following question:  What is the full name of the person who served in the Senate from his appointment in 1964 until becoming Vice President in 1977?
Walter Mondale