I believe it was Salmon Portland Chase, a man not known for his sense of humor, who once said the to him, “Douglas, no man will be ever be president who spells ‘Negro’ with two g’s.”
But Lyndon B. Johnson routinely and nearly daily used the dirty word according to more than one biographer. Became President anyway.
Sugar coated biography by Charles Peters said he genuinely started to like blacks when he was a young Texas school teacher assigned to poor areas. He vowed to someday help them.
In other books they said when riots broke out in cities like Detroit in July, 1967 LBJ sat at his desk and lamented to his staff and held the sides of his head and said “The n——s, the n-——s. After all I did for them how could they be doing this to me?”