Orcinus has assembled a 100 year history of American immigration scares. It's a good reference and a guide to what we can expect from the right wing.
It doesn't change my opinion on immigration though. I'm reserving judgment until I see more data on how it affects low wage earners. For now I think we ought to look at what Canada has done to get a big economic boost out of immigration. Canadian immigrants are not taking low wage jobs, they are selected for entrepreneurial behaviors and they create jobs at all wage ranges.