Race is moving to the forefront of the Democratic presidential primary after Pete Buttigieg used the debate stage Wednesday to connect his experiences as a gay man to black Americans’ long struggle against racism.

Kamala Harris countered Thursday that Buttigieg is “naive” and said he shouldn’t try to compare his life with what black Americans endure.

Buttigieg answered that he’s merely trying to speak up for one discriminated class as a member of another.

Harris is one of three black candidates seeking the Democratic nomination. Buttigieg is white and married his husband, Chasten, last year.

African Americans will play a critical role in choosing the nominee.

Separately Thursday, Joe Biden met with a group of black mayors, while Elizabeth Warren and Bernie Sanders campaigned on Atlanta’s historically black college campuses.