Mayor Mare has had a long and successful career as Mayor of Ponyville. Under her administration it has grown from a small farming village of Earth Ponies to what will soon be one of the most important and diverse cities in all Equestria. She has a lot to be proud of about her years as mayor.
But time does not stand still. She is getting much older, and she doesn't have the energy to accomplish what she once could. The growth of Ponyville increases her duties and responsibilities, and those are outgrowing what she can keep up with in her old age.
Faced with a new, younger challenger for her position she knows her days as mayor are numbered. As the votes are counted she has one primary thought going through her head----who is she if she isn't Mayor Mare anymore?
Thanks to Cosmic Eclipse and Alias_the_J for edits.