Arizona Legislative District 4 was redrawn in 2012 by the Independent Redistricting Commission. It is one of the larger districts by area, spanning 11,871 square miles and includes four counties: Yuma, Maricopa, Pima, and Pinal. 

Yuma County makes up the majority of registered voters with over 60%, while Maricopa has under 30%, Pima under 10%, and Pinal with less than 1%.