Not a chance. Michelle Obama's primary fashion difficulty is her very broad shoulders. She's got an amazon build. There's just no way she'll ever achieve a "feminine" look.
I was only half kidding when I said above that she'd look great in armor: she probably would, just as Venus and Serena Williams would.
There are probably a lot of designers out there who can make amazons look good. Unfortunately for her, the ones who can, are probably not politically connected or "Hollywood" enough to get the nod.
That's her main problem, in fact: there are such intense political overtones in everything related to Obama, that it's just not possible to go for the fashion unknowns who could make her look good. It's more important politically to drape her in big-name designs.
Venus and Serena got their overbites taken care of. They’ve really improved their appearances over the years.