August is a significant month in the history of equal voting rights.
On August 18, 1920, Tennessee became the 36th state to ratify the 19th Amendment, which was passed by Congress in 1919 and required three-fourths of states for ratification. (At that point, there were 48 states.)
As for Colorado, we were the 22nd state to ratify in December 1919. Our state is also notable in the suffrage movement for letting women vote since 1893, thanks to an election that enfranchised women by referendum.
Eight days later, on August 26, the Secretary of State signed a proclamation certifying the Amendment. This date would eventually be celebrated as Women's Equality Day, thanks to a Congressional designation in 1973 and a Presidential proclamation every year since.