Obama and Hillary endorse policies that keep wages artificially low. They pay people to come here and work for low wages. The Earned Income Tax Credit is money from the government paid to people including immigrants who work for low wages. It is an indirect subsidy to their employers.
Bringing poor people to the US and putting them on welfare increases the cost of caring for them by 1200%. If we had the money spend on poor immigrants today, we could easily end extreme poverty in the Western Hemisphere.