While I share my parties negative view of Illegal Immigration(against the law is against the law), I find the policies on legal immigration to be ill-informed, jingoistic, and completely contrary to the economic interests of the US.  Having a much more liberal immigration policy for H1B and other skilled, non criminal immigrants just makes sense.  More entrepreneurship.  More innovation based workers (many of whom are educated here).  And growing populations that add workers and productivity to the economy, as well as cultural richness to our communities. 
Having clear and feasible paths to citizenship for those who work, pay taxes, and do not commit crimes is an important and positive policy path.  If you care about economic growth and efficiency, you have to be pro-immigration.