Four Amendments to the U.S. Constitution specifically address “the right of citizens of the United States to vote”. They are:

15th Amendment - Prohibiting voter discrimination on the basis “of race, color or previous condition of servitude” — Ratified February 17, 1870

19th Amendment - Guaranteeing voting rights for women — Ratified August 28, 1920

24th Amendment - Outlawing poll taxes — Ratified January 23, 1964

26th Amendment - Lowering the voting age to 18 (from 21) — Ratified July 1, 1971