philadelphia billionaire environmental activist tom steyer expand political agenda beyond climate change embrace issue range immigration income inequality expect critical muster vote democrat hillary clinton november presidential election steyer four years ago leave hedge fund firm co-founded order devote full-time environmental activism say hop broad agenda nextgen climate organization would help undermine republican nominee donald trump deride new york real estate magnate policies dangerous delusional steyer direct nextgen main advocacy arm delve immigration racial justice wealth inequality education instead environmentalism good drive youth minority voter turnout nov. election talk broad group connect issue think stand without others steyer tell reuters interview sideline democratic national convention philadelphia explain shift nextgen already produce ads california attack trump immigration temperament one group young people film listen trump describe mexicans rapists drug dealers promise wall border another women look camera trump voice hear call women fat disgust ugly steyer say hop broad agenda nextgen would help undermine trump show respect steyer say trump spokesperson immediately available comment nextgen shift new issue begin months ago steyer say inspire work california progressive fair shake commission launch last year group high-profile activists academics former politicians focus wealth inequality state genesis extent allow us look deeply relate issue say nextgen spend 20 million far u.s. election likely spend least another 55 million election day steyer earn reputation america influential environmental advocate mix result crusade climate change despite money pour mobilize voters around issue steyer battle large-scale oil industry infrastructure project like keystone xl pipeline reject administration president barack obama last year seek bolster climate-friendly politicians 2014 nextgen pump around 75 million efforts support six climate-friendly democratic candidates mid-term elections two contest current presidential contest nextgen fall short aim make climate change critical issue eclipse voter rage issue include immigration economy national security reuters/ipsos poll show 25 percent likely american voters make choice basis candidate view climate change although agree unite state act combat steyer endorse clinton last month clinch democratic nomination follow heat battle senator bernie sanders vermont clinton say would seek advance renewable energy use boost regulation reduce u.s. consumption oil coal elect take word go prioritize steyer say trump call climate change hoax vow cut u.s. environmental regulation expand u.s. drill coal mine part bid win blue collar voters steyer call position dangerous would funny serious say activist steyer expand agenda bid defeat 'dangerous trump