Question

Every man and every woman in this Nation—regardless of party—who have the right to register and to vote, and the opportunity to register and to vote, have also the sacred obligation to register and to vote. For the free and secret ballot is the real keystone of our American Constitutional system.

This quotation addresses the point-of-view that

all adult citizens share a responsibility to vote.
only informed citizens should be allowed to vote.
political parties are a necessary part of the electoral process.
only certain people should be citizens of the United States.

Answer 1

all adult citizens share a responsibility to vote.

The quotation says everyone who has the right and opportunity to register and vote—regardless of party—has the "sacred obligation" to do so, emphasizing a universal duty to vote.