Kennedy , who represented Massachusetts in the United States Senate from 1953 to 1960 , had finished second on the vice presidential ballot of the 1956 Democratic National Convention . After Republican President Dwight D. Eisenhower defeated Adlai Stevenson II in the 1956 presidential election , Kennedy began to prepare a bid for the presidency in the 1960 election . In January 1960 , Kennedy formally announced his candidacy in that year 's presidential election . Senator Hubert Humphrey of Minnesota emerged as Kennedy 's primary challenger in the 1960 Democratic primaries , but Kennedy 's victory in the heavily-Protestant state of West Virginia prompted Humphrey 's withdrawal from the race . At the 1960 Democratic National Convention , Kennedy fended off challenges from Stevenson and Senator Lyndon B. Johnson of Texas to win the presidential nomination on the first ballot of the convention . Kennedy chose Johnson to be his vice-presidential running mate , despite opposition from many liberal delegates and Kennedy 's own staff , including his brother Robert F. Kennedy . Kennedy believed that Johnson 's presence on the ticket would appeal to Southern voters , and he thought that Johnson could serve as a valuable liaison to the Senate
1960 Democratic National Convention
1960 Democratic National Convention
Presidency of John F. Kennedy