Key read Dr. Seuss book One Fish, Two Fish, Red Fish, Blue Fish as Obama, capturing the politicians mannerisms and signature way of talking.
The comedian was then tasked with reading Dr. Seuss' Green Eggs and Ham as Sofia Vergara. Key raised his voice and attempted to mimic Vergara's accent.
"I understood you, so it wasn't good," DeGeneres joked about Key's Vergara impersonation.
Key is the narrator of Netflix's upcoming Green Eggs and Ham animated series that DeGeneres is executive producing. The show will arrive on the streaming service on Nov. 8.
"He's been a big part of my life," Key said about Dr. Seuss. "It was like one of these dreams that come true that you don't know you had," he continued about being featured on the series.