Out of all the potential duet partnerships out there, the one between Jim James & Kermit The Frog is probably the last that comes to mind.
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At the Newport Folk Festival this past weekend, a James & Kermith The Frog duet took place. The duo went on stage together during the Pete and Toshi Seeger tribute set "If I Had A Song", which was hosted and curated by The Decemberists multi-instrumentalist Chris Funk.
Singing the childhood classic "Rainbow Connection", James & Kermith The Frog were backed by a band including Funk, Janet Weiss of Sleater-Kinney, Benmont Tench of Tom Petty & The Heartbreakers, and Wilco's John Stirratt.