Professional politicians can not sustain long presidential primary campaigns without their superpacs funded by mega-rich donors.
And those meg-rich donors want the flow of cheap labor express of immigrants.
Even if Santorum is better than others on immigration, he still must accede to commands from his mega-rich donors.
Realistically, I see no path to stopping one million plus legal immigrants every year for many years, may be decades.
That is the primary goal of Barack Obama...to bring this country down to be no better than any others.