The gop need the cheap labor to work in their slaughter houses, pick crops for 12 hours a day, build houses, and work construction jobs. With the cheap labor comes big profits for corporations.  If the corporations were to raise wages the cost of goods would go up, even if the wages went up, most Americans would not do the work, how many people do you know that would bend over for 12 hours a day in the sun picking crops, or shooting a metal bolt into a cows head and then skinning alive a stunned cow.  I see Mexican workers building houses working from 7am to 7pm, I once saw a white crew frame a house, they started at 8am and left at 3pm everyday.