Alrighty Then: Whose Jobs Are Being Taken Away?

I recently visited my dad for Father's Day. He lives in San Antonio, Texas.

During that trip I couldn't help but notice several restaurants that seemed on the verge of shutting down. Dad and I came across a Mexican restaurant sporting a Help Wanted sign (in English, by the way). Granted its a single example - but witnessing this situation first hand, the.. rhetoric.. from those who would say illegal immigrants are taking away their jobs IMMEDIATELY came to mind. Not to mention hasty generalizations about good people with the simple intent to pursue happiness and to improve the quality of their family lives.

I didn't exactly see a mob of those petty people smashing down this door for work.

So tell me: about this immigration problem used as a political wedge issue - exactly whose jobs are being taken away?