You should have had an idea of DNC coverage from the start. The following URL links to the FTC FAQ page which the DNC site nearly begged everyone to read before you registered your numbers. See items 28 through 32.
 May 27th, 2012
This is a Public Interest Research Group (PIRG). I have no idea how they have my number, but I am on the Do not call registry. They call while I am not home, and don't leave a message. They have called numerous times since they started calling in the past few weeks. I have no idea if the Do not call registry covers non-profits at the time I am reporting this. I am filing a complaint with the FTC though for constant calling.
 May 24th, 2012