"We need to treat gun violence like the public health emergency that it is, and do real research about what works, what we could do to make this better, safer," Warren said at an event in Greenville. "The NRA holds Congress hostage. And the only way that is going to change is if we get out there and say, 'enough is enough, we're not doing this anymore.' So, I am ready to fight back against the NRA. Ready to fight for some change."