A member of the NAACP and active supporter of desegregation in Phoenix, Goldwater voted in favor of the Civil Rights Act of 1957 and the 24th Amendment to the U.S. Constitution, but reluctantly opposed the Civil Rights Act of 1964, believing one its provisions to be unconstitutional and a potential overreach of the federal government—a decision that considerably anguished him. In 1964, Goldwater mobilized a large conservative constituency to win the hard-fought Republican presidential primaries. Although raised as an Episcopalian, Goldwater was the first candidate of ethnically Jewish heritage to be nominated for president by a major American party (his father was Jewish). Goldwater's platform ultimately failed to gain the support of the electorate and he lost the 1964 presidential election to incumbent Democrat Lyndon B. Johnson by one of the largest margins in history. Goldwater returned to the Senate in 1969 and specialized in defense and foreign policy. As an elder statesman of the party, Goldwater successfully urged President Richard Nixon to resign in 1974 when evidence of a cover-up in the Watergate scandal became overwhelming and impeachment was imminent.