Transcript for On the trail, Democratic presidential candidates call for new gun control measures
state fair this week. The democratic candidates there for the ritual snacking on grilled pork and fried oreos. But this year, a more somber tone for the soapbox speeches. In the wake of the latest mass shootings. Our Mary Bruce on the trail for good morning, Mary. Reporter: Good morning, George. Amid all the fun and fried food here at the fair, we're seeing a very real shift in this campaign. The democratic candidates determined to keep up the pressure, are now having a serious debate on to tackle this rise in violence and demanding new gun reforms. Descending on this key state. How are you? Reporter: The presidential hopefuls snapping selfies, playing carnival games and flipping burgers. I think I can also flip Republicans. Reporter: But dominating the conversation -- gun violence. We need reasonable gun safety laws in our country including universal background checks and a renewal of the assault weapons ban. We need gun reform in the United States of America. And we need it now. Reporter: And they're taking on trump's rhetoric. Let's call this what it is. This is white nationalism. This is white supremacy. Reporter: The candidates greeted like rock stars at a gun safety forum on the sidelines of the fair. I come to you I know with these latest shootings in el Paso and Dayton, at a time of sorrow in our country but a time of real determination. We are going to make change, we're going to pass gun safety laws in this country. Aks, ars -- they have no place in our neighborhoods. In peacetime in the united States of America. They are for war Zones. Reporter: The day's emotions coming to the surface. I have 6-year-old and 3-year-old boys I was imagining -- I was imagining it was one of them that got shot. Reporter: Back in Washington under increasing pressure, the president is publicly pushing for stricter background checks. There's been no president that feels more strongly about the second amendment than I do. However, we need meaningful background checks so that sick people don't get guns. Reporter: And he says he can get Republicans and even the gun lobby on board, but in Iowa the candidates are skeptical. Quick to note that trump has made these calls before only to backtrack days later. Do you believe the president when he says he wants to see some kind of meaningful reforms? I find that fascinating when he says he's going to check with the NRA. Reporter: Republican leader Mitch Mcconnell is signaling he's interested in legislation but he's not calling congress back to Washington to tackle this. Do you get any sense this time around things are different? Mitch Mcconnell is starting to feel the heat, democracy is starting to show a little muscle out there and I think Mitch Mcconnell is getting a little bit worried. My view is, he ought to be a lot worry. Reporter: Voters here say they want to see action on this issue. Trump supporters even saying there's time for a change. The challenge for democratic candidates and voters is keeping this issue in the spotlight. Keeping up the pressure, of course congress isn't back in session for another month. George. Okay, Mary Bruce, thanks very much.
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