Which groups gained the right to vote by constitutional amendment in the 1900s?

Women (19th Amendment)

In 1919, the 19th Amendment was passed stating that "he right of citizens of the United States to vote shall not be denied or abridged by the United States or by any State on account of sex. Congress shall have power to enforce this article by appropriate legislation."

DC residents (23rd Amendment)

18 Year Olds (26th Amendment)

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