Final answer:
White southerners used economic power, violence, and electoral fraud to challenge Reconstruction, while engagement with progressive forces could have improved Reconstruction governments.
Step-by-step explanation:
To challenge Reconstruction, some white southerners leveraged economic power and resorted to White vigilante violence to retake political control from Republicans. They terrorized, assaulted, and murdered Black Republican officials with little consequence, using organisations like the Ku Klux Klan. Tactics at the polls included trickery and fraud to undermine the Fourteenth and Fifteenth Amendments, leading to a successful counterrevolution against Reconstruction policies starting in the 1860s.To try to improve Reconstruction governments, southerners could have worked with those advocating for change, including northern and southern whites and Blacks committed to Republican ideals. These individuals supported humanitarian efforts and were committed to creating a postwar South not under the control of former Confederates. Engagement with these progressive forces could have facilitated the advancement of equitable policies and infrastructure improvements made by Reconstruction governments such as the establishment of public education and investment in local services.