Final answer:
The STOP ERA movement led by Phyllis Schlafly changed the Republican Party by mobilizing conservative activists and shifting its emphasis towards small government and states' rights.
Step-by-step explanation:
The STOP ERA movement, led by Phyllis Schlafly, had a significant impact on the Republican Party in specific ways. By opposing the ratification of the Equal Rights Amendment (ERA), Schlafly and her movement mobilized conservative activists.
Their opposition to the ERA and their focus on issues such as abortion and traditional family values helped to shape the Republican Party's platform and brought in new supporters.
Additionally, the movement played a role in shifting the Republican Party's emphasis towards small government and states' rights, which contributed to the party's realignment and the Reagan Revolution.