On Aug. 2, Amazon set out to hire 50,000 people, with a dozen job fairs held at sites around the United States. So far it has received 20,000 applications.

Whether the company meets its recruiting goal will be an interesting litmus test—not only for Amazon but the US itself. The country is supposedly so hard up for low-wage jobs that the Trump administration, claiming an interest in protecting opportunities for the poorest American workers, has drawn up a plan to seriously scale back legal immigration by low-wage foreigners.

But warehouses in the US are frequently beset by job vacancies, even as more tasks get turned over to robot labor. “Most businesses in the system have a deficit of workers,” Bruce Welty, the founder of both an e-commerce logistics company and a startup that makes robots for warehouses, told Quartz in a February interview. “These are not great jobs, and they’re not easy to fill.”

The US unemployment rate fell to a 16-year low in May and was only slightly higher in June. Beyond being squeezed by a tighter labor market, competition for warehouse workers may be particularly high because the facilities often cluster together in areas with good access to commercial transportation. In any case, the pressure seems to be pushing up pay for warehouses jobs, with big employers like Walmart lifting wages for hundreds of thousands of workers.

The Wall Street Journal reports that full-time warehouse work at Amazon pays $13 to $14 an hour in Baltimore, Maryland, and $11 an hour near Tampa, Florida. Amazon also offers its warehouse employees perks such as college-tuition reimbursement.

Amazon says the 20,000 applications it received yesterday (Amazon Jobs Day, as the company refers to it) was a single-day recruiting record. The company is continuing to accept and process applications.

The current hiring drive is part of an overall plan to add 130,000 US employees— 100,000 of them in full-time roles and 30,000 in part-time positions—over the next year, a significant increase from the 180,000 US workers it employed at the end of last year.