The only thing I would want to add is a minimum wage increase would cause employment to decrease holding all else equal, so an increase in supply would not be observed unless something else were at play.
Oh, of course, I was talking about the two separate cases of wage increases due to productivity increases (the guy maintaining the widget machine makes more than the guy who used to hand-stamp widgets) and wage increases due to minimum wage increases (all factories must now pay workers $15/hour for making one $8 widget every two hours).
