Final answer:
The primary opposition to the Civil Rights Act of 1964 came predominantly from the Democrats, particularly the conservative southern Democrats known as Dixiecrats, who opposed societal integration and equality.
Step-by-step explanation:
The Civil Rights Act of 1964 was a landmark legislation in the United States which sought to end various forms of discrimination including in settings of employment and education. Analysing historical sources and data, it is clear that the opposition to the Act primarily came from southern Democrats, who were in essence, Dixiecrats (conservative Democrats who opposed integration and the goals of the Civil Rights Movement).
This group opposed the promotion of racial integration and societal equality which they believed violated social norms and state sovereignty. As the Democratic Party increasingly took steps towards supporting civil rights, a rift developed with these southern Democrats which eventually led them to switch their alliance to the Republican Party by the 1970s. The Republicans as such did not actively oppose the Civil Rights Act of 1964 as a party.
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