Summary: This Labor Day, several 2020 Democratic presidential candidates appeared more focused on gun safety than the holiday's typical topics of unions, wages and jobs. Former Vice President Joe Biden and Sen. Amy Klobuchar blasted Republicans for lack of action on guns two days after Texas' second mass shooting in a month. And on CNN Sunday, Beto O'Rourke slammed U.S. gun laws. Lisa Desjardins reports.
