One of Bernie Sanders talking points on the campaign trail is that the “real” unemployment rate is much higher than the official 4.9% cited by the Labor Department, and he should know.

That’s because Sander’s biggest source of fundraising support comes from the retired or unemployed, according to filings with the Federal Election Commission, as reported by Bloomberg.

$16 million of the $73 million the candidate raised in 2015 came from individual donors who said they were without jobs, according to the report.

This group of people has good reason to support the Vermont Senator. He is proposing to expand Social Security, to the tune of $65 more per month on average, financed by raising payroll taxes on wealthy wage earnings. He’s also vowed to get the unemployed working again through a $1 trillion infrastructure plan the campaign says will create 13 million “good-paying” jobs.

 

The Sanders campaign has made much of the fact that almost two-thirds of its contributions have come from small donations of $200 or less.

Fortune has reached out to the Sanders campaign for comment and will update the piece if it responds.