"For six full years, through three Congresses under President Wilson's power, the continual Democratic resistance, meandering, delays, deceits had left us still disfranchised. A world war had come and gone during this span of effort. Vast millions had died in pursuit of liberty. A Czar and a Kaiser had been deposed. The Russian people had revolutionized their whole social and economic system. And here in the United States of America we couldn't even wrest from the leader of democracy and his poor miserable associates the first step toward our political liberty-the passage of an amendment through Congress, submitting the question of democracy to the states! What a magnificent thing it was for those women to rebel! Their solitary steadfastness to their objective stands out in this world of confused ideals and half hearted actions, clear and lonely and superb!" --Doris Stevens, Jailed For Freedom |

Our task was, therefore, to induce the President to call a special session of Congress at the earliest possible moment, and to see that he did not relax his efforts toward the last vote."
The National Women's Party succeeded at both of these endeavors. Protests were held in Boston and New York and the uproar that resulted was splashed across the newspaper headlines. Wilson agreed to a special session to vote on the amendment and ensured that it would pass.
Putting the Rat in Ratification
On June 4, 1919, after 40 years—and much effort and debate—Congress passed, by a two-thirds vote of both houses, that proposed amendment. It was then up to the states to ratify it. Many states quickly approved the amendment, and by the end of March 1920, it was just one state shy of ratification.
Mississippi could have been the final vote needed to make the amendment law, but the state rejected it on March 29.
The amendment still needed one more state for ratification when the Tennessee legislature met in special session that summer.
The Tennessee Senate passed the amendment, so ratification rested with the Tennessee House of Representatives. After weeks of intense lobbying and debate, on August 18, 1920, a motion to table the amendment was defeated with a 48-48 tie.
The speaker then called the for the vote to ratify. It seemed certain the result would be another deadlock, but that morning a son received a letter from his mother that changed everything.
The son was Harry T. Burn, a 24-year-old representative from East Tennessee. Just two years earlier Burn had become the youngest to be elected to the state’s legislature. Burn, who had been seemingly solidly in the anti-suffrage camp, received a seven page letter from his mother asking him to support the amendment.
Dear Son, . . . Hurray and vote for Suffrage and don’t keep them in doubt. I noticed Chandlers’ speech, it was very bitter. I’ve been waiting to see how you stood but have not seen anything yet. . . . Don’t forget to be a good boy, and help Mrs. “Thomas Catt” with her “Rats.” Is she the one that put rat in ratification, Ha! No more from mama this time. With lots of love, Mama.
Burn had hoped the issue wouldn’t rest with him—he supported suffrage himself, but his constituents were opposed, and he faced an election that fall. Burn was torn, and when the issue came to vote he blurted out “aye,” without thinking, thus breaking the tie.
The Tennessee legislative had passed the amendment making it law of the land.
https://prologue.blogs.archives.gov/2017/08/01/putting-the-rat-in-ratification-tennessees-role-in-the-19th-amendment/