[dba-SQLServer] Normalizing a text field

I have a spreadsheet with a zip column and a column with 0 to many 
cities in the format Name1, St Name2, St Name3, St

Notice that there is no "field delimiter" between St (state) and the 
next city name.

Is there any way in SQL to do this or is this a job for code?  I can 
write the code, but I am lost on doing this in SQL.

-- 
John W. Colby
www.ColbyConsulting.com