That's Jon Stewart, the Daily Show guy. John Stewart was the Kingston Trio guy. Don't feel bad, the internet doesn't know which is which either. I search on one and the other pops up.
An old, old show. Started on radio in the early 1950s was adapted for TV a few years later. It was on TV for about 20 years, followed by a few TV movies. There's a Pluto channel that carries it 24/7.