Take a poor, generally uneducated, immigrant class escaping poverty and crime who speak differently. They will work in many jobs considered low-class or extremely blue-collar. They are generally Catholic and are associated with crime in popular media.
In the 1800s they are the Irish, in the 2000s they are the Mexicans/Central Americans. Seriously, learn some Spanish, its coming...
I was hoping they would learn English, and assimilate with the community, but when your an ILLEGAL alien that is here without documentation, I guess that's a pipe dream.
The assumption they will work low-class or extremely blue collar jobs that Americans won't is Bull Hockey.