Final answer:
The black vote was significant in local elections, but not a priority in national politics. Urban black voters were often registered in equal or greater numbers than the nationwide average by 1970. The impact of black votes in certain states in the 2020 election cannot be determined without specific information.
Step-by-step explanation:
The black vote was significant in many Northern cities, but in terms of national politics, the black population outside the South represented only 1 percent of the total population. Both the Republican and Democratic parties didn't prioritize the needs of African Americans if it risked losing votes in the white-only elections of the South. In recent decades, a new generation of Democratic leaders began to court black voters.
In 1970, urban black voters were often registered in equal or greater numbers than the nationwide average. This led to many black candidates winning election to city offices, and several major cities elected African American mayors. Meanwhile, efforts were made to increase African American voter registration, resulting in more black elected officials.
If black votes were present in certain states in the 2020 election, it is impossible to determine who would have won without specific information on voter preferences and outcomes in those states.