Today's Piano Puzzler

From the archives, the contestants on today's Piano Puzzler are Beau Smith Pacheco from Addleboro, Massachusetts.  For th​e longest time, I had hard time picking out the hidden song, though I thought I heard a couple possibilities.  But a long ways in, it finally became absolutely clear, and I knew I had it right.  As for the composer style, it danced between several possibilities...all of which were wrong.  But the composer is very popular -- and one of my favorites.  I just didn't think he wrote anything like this.  One quibble -- not about the contest, but the discussion afterwards.  The contestants didn't know the hidden song at all, though it's famous with several reasons why its pedigree should have helped -- yet neither host Fred Child or pianist Bruce Adolphe explained any of them.  They only gave the name of the song.  Not its larger context or perhaps who else famously recorded it, or maybe where it's from.  (Sorry, I don't want to say more to give it away for those playing along.)  At which point, if they had, the contestants might have said, "Ooohhhhh!  Okay!!  NOW I know what it is."