washington come trade policy hillary clinton take heat side democratic national convention week clinton formally accept party presidential nomination opposition trade deal plaster button scrawl sign chant delegate many worry past support 1994 north american free trade agreement trans-pacific partnership still await congressional approval things unlikely get easy clinton say stance trade evolve oppose tpp enough protect job want change nafta trade deal husband bill clinton sign presidency allow republican opponent donald trump question credibility paint clinton evolve position desperate attempt catch tough stance trump vow force canada mexico renegotiate nafta label job killer real estate developer also say would pull unite state 12-nation tpp even among democrats doubt clinton resolve particularly among supporters former democratic rival bernie sanders u.s. senator vermont whose opposition trade deal feature prominently speeches democratic primary season concern trade display convention speech deliver wednesday night clinton run mate tim kaine u.s. senator virginia support tpp delegate wave anti-tpp placard kaine speak even though change position join clinton ticket larry cohen senior adviser sanders say trade absolutely danger clinton race trump say show commitment oppose make pronouncements trump campaign smart enough exploit issue cohen say sanders supporters say intend keep fight tpp november election via new group call revolution dedicate champion issue sanders push campaign trail frustration post-recession recovery fail translate good wag opportunities million work americans become one lead theme 2016 presidential campaign reuters/ipsos poll take march show 65 percent democrats 70 percent republicans believe trade cost u.s. job even though many also agree trade help keep cost goods low richard trumka president afl-cio labor federation tell reuters clinton tell major unions endorse want re-work nafta echo similar comment dennis williams president unite auto workers union trumka say clinton campaign tell would take whole new approach trade say convince could trust issue give lip service commit say consult clinton talk unions regard nafta senior mexican government official say tpp already provide unite state platform strengthen right workers compare nafta although u.s. union activists say new pact weaken rather strengthen workers protection solution hand back official say note congress yet ratify tpp official add would mexico interest strengthen rule origin tpp determine country product come sometimes allow foreign components caution however re-opening trade deal highly complex undertake morris fiorina political science professor stanford university say clinton try address workers concern avoid wholesale dismissal free trade advise suggest try thread needle explain free trade great benefit country whole past pending agreements adequately recognize compensate losers remedy failure fiorina say however nuanced approach may prove self-defeating light trump challenge internal dissent robin biro field director democratic party atlanta clinton supporter say tpp make break issue clinton attract democrats vote sanders primary go get support bernie people come strongly issue biro say mistrust clinton trade shadow democratic convention