Illegal Immigration in America?

Recently i heard a number that astonished me. It was that illegal immigrants cost the US an excess of 300 billion a year. Next i heard that to remove all the illegal immigrants would only cost us about 250 billion. Now if we removed all of the illegal aliens then this would reduce the cost the US government spends. Open up jobs for a extremely large number of people and than obama would not have to try to redistribute the wealth. Any Response?