brasilia former brazilian senator environmental minister marina silva say saturday would seek party nomination run president next year silva announce plan meet sustainability network party rede would officially nominate national convention april 59-year-old environmentalist bear rubber-tapping community amazon rainforest minister former president luiz inacio lula da silva run previous two presidential elections never make second-round vote silva say would seek party nomination brazilians want country free corruption ethical bear deliver supporters praise brazil principled politician could play large role next election since early 2014 brazilian prosecutors police carry unprecedented anti-corruption drive reveal political graft touch every major party silva s. silva remain commit fiscal responsibility inflation target float exchange rate so-called tripod economic policies give brazil stability period rampant inflation erratic growth 1990s late election survey conduct respect datafolha poll institute publish saturday folha de s.paulo newspaper website silva rank third 10 percent respondents say would vote poll include lula possible candidate lula convict corruption trial july high court uphold conviction october election could run without lula datafolha poll silva trail right-wing candidate jair bolsonaro federal lawmaker 21 percent approval compare 16 percent datafolha interview 2,765 voters across brazil nov. 29-30. poll two-percentage-point margin error 2010 election silva green party take surprise 20 percent first-round vote enough push runoff eventual winner dilma rousseff 2014 run vice president brazilian socialist party ticket head eduardo campos die campaign plane crash two months election silva take spot 21 percent first round miss runoff brazil environmentalist marina silva run president 2018