"It's been an incredible appeal what he has had," Progress Iowa executive director Matt Sinovic said of Sanders, appearing on "Breitbart News Sunday" on Sirus/XM 125 with host Steve K. Bannon and Washington political editor Matt Boyle, which was broadcasting from Des Moines. Progress Iowa is a nonprofit organization that describes itself as "powered by a community of more than 30,000 progressives, focused on research, education, and advocacy." Sinovic described Sanders as "a movement candidate that has caught fire" competing against Clinton, who has a "broad, broad base of support" culled from a prior campaign.