Some parts of the original federal design were modified under pressure from citizens. Two changes are highlighted here.
The Constitution originally empowered the state legislatures under Article 1, Section 3 to choose whom they wanted to represent their states in the Senate. This power was transferred to state citizens in 1913 when a sufficient number of states ratified the Seventeenth Amendment.
The apportionment of seats in the House of Representatives by state populations was initially tainted by the “three-fifths” compromise with the slave states. Under the compromise, three-fifths of each enslaved person would be counted for determining shares of direct taxation and representation in the House of Representatives. This arrangement was revoked after the Fourteenth Amendment defined citizens as all persons born in the United States of America or naturalized to it.
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