What you need to do is tell them you do not want to receive their calls, and make sure you do a opt out with all the political parties. Then, if you receive calls, go that persons web site and under their contact us page, write them and tell them to place you on their internal dnc list and also there is a political do not call you can sign up for. I did and also tell them to use that list and give them the url for it. I have not gotten any calls for years now. Not even political survey's. So it does help to follow the steps.
http://stoppoliticalcalls.org/index.php
Call Blocker - either a device or phone will also be a big help!
I called the number back, and a recording told me that it was used for "political purposes." I was able to leave a message asking that they not call back again.
I'm getting calls, too. I'm guessing these scumbags are starting to use numbers within the same area code to increase the chances of people actually answering. I didn't. They didn't leave a message.
Most likely a solicitor. I have no debts nor collections, so I assume they're trying to sell me something. They have called twice and left a 3-second voicemail with no sound both times. My iPhone says "Birmingham, MI"