you know what else harms and kills children, assault rifles do. [ applause ] maybe -- maybe if the nra starts flavoring those, you'll ban them, too. >> you know, he's making jokes. but 38 people killed in mass shootings in the last month. so, such quick action on one and nothing on the other. >> there's no second amendment right to smoking in this country, though. on tap, tonight, debate number three for the democrats. and this time around, it's a one-night event. here's the ten candidates who qualified. for many of them, it could be the final opportunity to break through. and we'll see joe biden and elizabeth warren, side-by-side on the same stage. jeff zeleny is already in houston. >> reporter: dave and christine, the third presidential debate is tonight in houston.