AMES, Iowa — Democratic presidential candidate Hillary Rodham Clinton planned to unveil a plan on Sunday aimed at combating climate change that includes revisions in the tax code to promote renewable energy. In Iowa, the nation's second-leading wind energy producer, Clinton said people are “just not paying attention” if they don't acknowledge climate change. “This is not complicated folks,” the former secretary of state told more than 200 people at Iowa State University. “I'm just a grandmother with two eyes and a brain. And I know we're facing huge problem.” Climate change has become a key issue in the Democratic presidential primary, where Clinton is the heavy favorite. Though Clinton hinted that under her plan the coal industry would face changes, she said the federal government would help the industry. Changes in the tax code aimed at promoting renewable energy and transitioning away from coal is a tricky political position in key places in the country. Southeast Ohio and western Pennsylvania, states that have been pivotal in recent elections, remain the home of key coal-producing areas. Sen. Bernie Sanders, a Democratic candidate for president to the left of Clinton who has been attracting increasingly larger crowds, told voters Sunday in Louisiana, where a gunman opened fire in a movie theater on Thursday night, that common ground can be found on gun control. “Coming from a rural state, I think I can communicate with folks coming from urban states where guns mean different things than they do in Vermont where it's used for hunting,” Sanders said. “That's where we've got to go. We don't have to argue with each other and yell at each other. We need a common sense solution.” Sanders said Americans must find common ground on gun laws, such as improved background checks to prevent gun sales to people with criminal records or a history of mental instability or domestic abuse. He capped a weekend of Louisiana events with a rally in a suburban New Orleans convention hall that drew close to 4,000 people. Former Maryland Gov. Martin O'Malley, also seeking the 2016 Democratic presidential nomination, noted Sunday that he unveiled a climate change plan in Iowa. Campaign aides to O'Malley said that as governor, he made climate change a top priority, doubled Maryland's renewable fuel production, and reduced greenhouse gases by 10 percent during his two terms. — AP