Numerous Americans accept him as uncle (3)

I believe the answer is:

sam

I'm a little stuck... Click here to teach me more about this clue!

'uncle' is the definition.
(Uncle Sam is an example)

'numerous americans accept him' is the wordplay.
'SAM' is hidden within the letters.
But, I am unsure how this is indicated.

'as' acts as a link.

Can you help me to learn more?

(Other definitions for sam that I've seen before include "Boy" , "together once" , "Casablanca piano player" , "Uncle" .)

I've seen this clue in the Evening Standard.

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