Hubert Horatio Humphrey Jr. (May 27, 1911 - January 13, 1978) was an American politician 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. He was the Democratic Party's nominee in the 1968 presidential election, losing to Republican nominee Richard Nixon.

Humphrey and his running mate, Ed Muskie, who had not entered any of the 13 state primary elections, went on to win the Democratic nomination at the party convention in Chicago, Illinois even though 80 percent of the primary voters had been for anti-war candidates, the delegates had defeated the peace plank by 1,567 3/4  to 1,041 1/4 . Unfortunately for Humphrey and his campaign, in Grant Park, just five miles south of International Amphitheater convention hall (closed 1999), and at other sites near downtown Chicago, there were gatherings and protests by the thousands of antiwar demonstrators, many of whom favored McCarthy, George McGovern, or other "anti-war" candidates. These protesters - most of them young college students - were attacked and beaten on live television by Chicago police, actions which merely amplified the growing feelings of unrest in the general public.  Humphrey's inaction during these activities along with President Johnson and Chicago Mayor Richard Daley's behind the scenes convention influencing, public backlash from securing the presidential nomination without entering a single primary, as well as Humphrey refusal to meet McCarthy half way on his demands, resulting in McCarthy's lack of full endorsement of Humphrey, highlighted turmoil in the Democratic party's base that proved to be too much for Humphrey to overcome in time for the general election. The combination of the unpopularity of Johnson, the Chicago demonstrations, and the discouragement of liberals and African-Americans when both Robert F. Kennedy and Martin Luther King Jr. were assassinated during the election year, were all contributing factors that caused him to eventually lose the election to former Vice President Nixon.  Although he lost the election by less than 1% of the popular vote, 43.4% for Nixon (31,783,783 votes) to 42.7% (31,271,839 votes) for Humphrey, with 13.5% (9,901,118 votes) for George Wallace, Humphrey carried just 13 states with 191 electoral college votes. Richard Nixon carried 32 states and 301 electoral votes, and Wallace carried 5 states in the South and 46 electoral votes (270 were needed to win). In his concession speech, Humphrey said: "I have done my best. I have lost, Mr. Nixon has won. The democratic process has worked its will."

Using a quote from the above article, answer the following question: Who was the running mate of Humphrey?
Ed Muskie,