Yes, I am firmly of the opinion that you can have a workout with classical music. I myself, before suffering a slipped disc from July 2012 - August 2013, did a leg extensions set based on the theory "if you do eleven, then you need to increase the weight" and managed (without realising it) to get all the way to 70kg (when my previous best was 55kg) and the only difference between the two sessions was this:

 

 

Namely "Mars" from the Planets Suite by Gustav Holst playing on the television which had been tuned to a classical music radio station

Music can really motivate us at a very deep level. It definitely works for me. I think at the end of the day it just helps you focus and not think about outside distractions.