Martin O’Malley, Jose Vargas, Tia Oso

As dozens protesters shout, Tia Oso of the National Coordinator for Black Immigration Network, center, walks up on stage interrupting Democratic presidential candidate, former Maryland Gov. Martin O’Malley, right, as moderator Jose Vargas watches at left, during the Netroots Nation town hall meeting, Saturday, July 18, 2015, in Phoenix. (AP Photo/Ross D. Franklin)