The endorsement was made official in a radio ad airing in South Carolina in the lead up to the state’s Democratic primary, reports the Daily Beast. The ad features Lee reading the following message:

This is your dude, Spike Lee. And you know that I know that you know that the system is rigged! And for too long we’ve given our votes to corporate puppets. That’s why I am officially endorsing my brother, Bernie Sanders. When Bernie gets into the White House, he will do the right thing!

The Daily Beast notes that Lee also praises Sanders’ record of fighting for civil rights.

Lee is generally well respected in the black community, who make up more than half of Democratic primary voters in South Carolina. His films have often themes of racial tension and discrimination, and Sanders’ is clearly hoping Lee’s endorsement will help bring the important constituency to his side.