That’s something that probably deserves a whole post instead of a quick liveblog take! (And Harry has dived into this.) The short answer is that Sanders would probably cost the Democrats a couple of percentage points, other things held equal, but not necessarily produce a McGovern/Goldwater type disaster. The longer answer involves mentioning that McGovern and Goldwater weren’t just “extreme” ideologically but also very divisive nominees, so some of it would depend on how much Sanders was able to unite the Democratic Party behind him.
