A week ago there were six legitimate contestants for the democratic nomination in the United States. Today there are basically two—and according to a lot of pundits, there's really only one: Joe Biden, back from the campaign scrap heap to champion the moderates. How did that happen so quickly? What does it mean for this fall's election? Can Bernie Sanders claw his way back to the top? What the heck happened to Elizabeth Warren? And to Canadians...what's the difference between them all? And would any U.S. president—even a second term of Donald Trump—materially change the relationship between the two countries? GUEST: Ryan Hurl, political science, University of Toronto