Idiom: to have one thing going for smb

[marenparn]

Please, could someone give me the exact meaning of the idiom 'to have one thing going for smb'

I guess it means something like 'there is at least one positive thing about smb'

Thanks a lot in advance

Maren

[David L.]

John: "He doesn't have much chance of getting the job he's applied for."
Mary: "At least he has one thing going for him: he's from a minority group!"