"I Wonder Why" is a doo-wop song, written by Melvin Anderson and Ricardo Weeks (lyrics), and first recorded by Dion and the Belmonts (released as Laurie Records' first single, number 3013), becoming the group's first national pop chart hit, in 1958. It is sung from the point of view of a man telling his girlfriend that he loves her but does not know why. The song is noted for Carlo Mastrangelo singing the bass part in rhythm. The song was used in the film A Bronx Tale, in the pilot episode of the television series The Sopranos, and in John Carpenter's adaption of Stephen King's Christine. A cover was sung by Nicolas Cage in Peggy Sue Got Married. A cover was also sung by Showaddywaddy in 1977, reaching number 2 in the UK Single Chart.

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