One year out, tumult dominates wide open US 2016 race

Americans elect a new president one year from Sunday, with the names Clinton, Trump, Carson and Bush at the fore. The race is wide open, with Democrats seeking a historic treble and Republicans suffering an identity crisis. As the country gears up for a 12-month campaign slog -- starting with a dash to the first statewide primary contests in February -- concern has risen over Mideast violence and police-citizen tensions at home, and debate swirls over immigration, guns and income inequality.