Expand that Australian state
Retina, 135 121 bytes

13 bytes golfed thanks to @Neil by using clever space insertion tactics, which inspired one more byte being golfed

AS
asmania
^W
Western 
NT
NorthernT
T$
 Territory
A
Australia
aC
an Capital
IC
ictoria
LD
ueensland
SW
ew SWales
S
South 


Try it online!

Note the trailing spaces on the fourth and the last lines.