How did the 19th amendment gain approval from the public and eventually get the votes needed to become a part of the constitution?

The approval that the 19th amendment needed to gain was majority related in to some of the states where already few afroamericans (mens) can vote. This acts initiate the women's rights movements.

Explanation:

However when the afro american community start to see that this promise from the government was thruth in certain states (in 1868 with the 14th amendmend) there were when gain the importance for the goverment as study the results of this fact, also thanks to the spokesman, the government agreement refers womans were the protagonist of this amendment and they count like a valid persons to suffrage also with the same rights. "shall not be denied or abridged by the United States or by any state on account of sex" But remember most of the states continued with the restriction to women's sufffrages.