When they called last month, I added them to my phone book as "Survey" and so did not bother to answer when they called back yesterday.
If you call them back, you won't be able to speak to a live person. I guess the only way to get on their do not call list is to go to their website and send them an email.
Sadly, these "survey" calls are legal. However, once you tell them to stop calling, they cannot call you again. If they do, they can be reported to the donotcall.gov website.
I got a pre-recorded message after I let it go to voicemail. It does appear to be a survey for Better Chicago, and they mentioned something about my opinions on Education.
Automated survey conducted by the For a Better Chicago PAC. Caller ID said, "US Cellular." I called the number back and left a message asking to be taken off of their calling list.