Sopranos cast short of a godfather? (7)

I believe the answer is:

sponsor

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'godfather?' is the definition.
(godfather is a kind of sponsor)

I cannot understand how the rest of the clue works.

(Other definitions for sponsor that I've seen before include "One funding an event" , "Back financially" , "Supporter or champion" , "Patron or backer" , "One who pays costs for event" .)

I've seen this clue in The Times.

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