One change in U.S. politics in the 1960s and the 1970s that contributed to Reagan's victory was the increased liberalization of domestic government policy.
The 1960s and the 1970s saw an increasingly liberal America in the form of the Civil Rights Movement, anti-war protests, feminism, and abortion becoming legal.
Many Americans felt that their society was undergoing moral decay and so when Reagan campaigned under the banner of Conservatism as the "New Right" many people voted for him with eagerness.
Find out more on the New Right at https://brainly.com/question/455769.