Arguably they are the same thing by definition. The degree and intensity of the scam just varies a bit between well-known companies on one end, and the "kid had an accident" and tech support scams on the other.
Annoyingly enough, first-party scams (i.e. your own phone operator trying to dupe you into something) are somewhere in the middle of this spectrum. So are political calls you mention.
Because I'm on the DNC list in the US, I don't get many/any legal telemarketing calls.
The political stuff is really annoying because very little of it is directly from the campaigns themselves. It's all push polls and PACs and whatnot.