I also received a call from this number and was blocked after one ring from the free service I have installed on my landline. Whether they attempt to call again remains to be seen. Still won't get through. Oh well.
It is currently a political call asking for your support of Sen. Bernie Sanders. No need to freak out, if you are not interested don't answer it or whatever.
Political calls are exempt from the Do Not Call list. Same goes with charities, phone surveys, and bill collectors. The only calls that the DNC list should stop are telemarketers, unless you signed up for something.