Much of Ken Martin’s four months as head of the Democratic National Committee have been engulfed in a feud with David Hogg, the Gen Z activist who vowed to back primary challengers to Democratic incumbents in conflict with other party leaders.

David Hogg, who was at the center of controversy over his efforts to primary incumbents in Congress, is leaving the Democratic National Committee.

The move follows repeated bouts of infighting centering on the Gen Z activist’s pledge to involve himself in party primaries and support challenges to some incumbents.