I don't think that Lea Michele deserves a nomination, and I am neither blind nor stupid.
She's fine in the part, to be sure - but she's not brilliant. She's not fantastic. She's suitable, and the constraints of the role (and the size of the role) don't allow her to blossom and shine over other contendors like Chenoweth and Ebersole.
In response to why Ebersole should win, it's not really that her impersonation is dead on. Because it's not. If you know the documentary inside and out, you will know that Ebersole's inflection, dialect, accent, etc. is way off.
It's not about impersonation for me. It's not about Ebersole sounding just like Edie Beale - because she doesn't.
It's about her having an uncanny connection with Edie, and creating a subtext involving the character that may not have even happen. She cultivated something beautiful. Although Ebersole is playing a real person, she is very much playing an imagined person. Her connection to her, the material, and to the message is almost unspeakably beautiful.
"If you are going to do something, do it well. And leave something witchy."
-Charlie Manson
