This is a company called Donor Services Group. Orgs hire DSG to make calls for them or solicit donations. Today I got one from this number saying they are with MoveOn.org. Next month it might be the Humane Society or the Police Officer's Fund or whatever. I'm tired of telemarketing calls too, but there's no harm in listening if you want, donating if you want, or politely declining if you want.
If they are calling your cell phone, you should be able to add it to a reject list. On my phone, I go to the call in my log and then touch the screen at the top right where there are 3 vertical dots. One of the options is Add to Auto Reject List. They can still call you, but it won't ring or connect to you. It just shows up as a missed call.
SPAM-TELEMARKETERS! They call 5x's/day. Sometimes leave messages with with just sounds of busy background talking from a call center. I block them from my iphone but they just keep altering the # by a few digits. MAKE THEM STOP!
This person left a voice mail saying, "What do you think about what Kathy Griffin did?" Then she laughed. Not sure what that was about, but the caller ID did say "Donor Services." I don't answer calls I don't recognize.