Somewhere between like Rocky and Cosby
His style is between determined (Rocky) and comedic (Cosby); the Cosby reference transitions well into the next line.
This reference is one of many biracial references Macklemore makes about himself because he’s a white rapper in a predominantly Black art of hiphop. Here’s another example
To help improve the meaning of these lyrics, visit "Can't Hold Us" by Macklemore and Ryan Lewis (Ft. Ray Dalton) Lyrics and leave a comment on the lyrics box