McArdle thinks not:
Social Security does not just depend on the existing pool of workers; it depends on their output. You cannot keep the pyramid going by replacing each retiring public accountant with 1.5 cleaning ladies and carpenters. While there are certainly lots of highly skilled immigrants who want to come here, it's far from clear that the math works for social security. To be clear, that's not a brief against letting lower-skilled workers come in; they are a valuable complement to higher-skilled workers. But they cannot en masse shore up social security's finances, especially since they too will eventually collect it–and social security's benefit structure is progressive.
The Dish 