[QUOTE=HeHateY]Really? How much payroll tax can they generate if they are paid cash under the table? And how do they get Social Security numbers except via a form of identity theft?

You would be surprised by how many undocumented are not paid under the table. Many undocumented workers are paid by check on the payroll and they have social security taxes withdrawn, money they will never see. I've read that they contribute millions of dollars annually to the SS coffers. Yes, they are using fake social security cards. You can walk down Mission Street here in San Francisco any day of the week and hear guys say "micas, micas" (Mexican Spanish for I.D. cards) which they sell for about $100.00 for a fake s.s. card and fake CA I.D. card.