A new Hillary Clinton ad proposing gun control measures features the pastor of the Charleston, South Carolina church where nine congregants were murdered in a race-fueled massacre, leading to a nationwide crisis over guns and the Confederate flag.

Last June, the wife of Rev. Anthony Thompson was killed when 21-year-old Dylann Roof attended a Bible study in the basement of the historically black Emanuel A.M.E. church and opened fire. Roof told survivors that he was doing this because blacks were "taking over the world" and committing crimes against whites. As the media, in typical fashion, lambasted guns in the wake of the mass shooting, a picture of Roof holding a Confederate flag surfaced days later, creating a parallel urgency to remove all vestiges of the Confederate symbol across America in the hopes that doing so, like taking away guns, might also curb violence.

And in that same spirit, Clinton releases the ad, "Standing." In it, Rev. Thompson relives the tragic phone call that day when he was notified of the shooting:

The first thing came to my mind was, "We need to make some changes." Hillary is really committed to making sure that the guns don't get into the wrong hands and is standing with the president to get stronger gun laws so no family ever has to go through anything like this again.

The ad has been strategically released in the weeks leading up to the South Carolina primary.

According to the Washington Examiner, Thompson's children have also endorsed Clinton and she has used their stories for her campaign website.