Don't take my word for it.
Obama says so.
Or at least he did in his 2006 book The Audacity of Hope:
"If this huge influx of mostly low-skill workers provides some benefits to the economy as a whole—especially by keeping our workforce young, in contrast to an increasingly geriatric Europe and Japan—it also threatens to depress further the wages of blue-collar Americans and put strains on an already overburdened safety net.”There are already millions of young American citizens out of work. Millions more can only find minimum wage part time jobs.
Yet Obama now wants to welcome millions more immigrants into the work force to compete against American citizens young and old. And he says he'll do it on his own if Congress won't become complicit in his push to undermine the financial security of American citizens.