Warren leads Biden for first time in a US primary race: poll

Presidential hopeful Elizabeth Warren has overtaken former vice president Joe Biden in the key state of Iowa for the first time in the race for the Democratic presidential nomination, a new poll out Sunday showed.The Des Moines Register/CNN poll had Warren with 22 percent of the vote among likely participants in the Iowa caucuses, compared to 20 percent for Biden and 11 percent for Bernie Sanders.Biden had until now has been the dominant frontrunner in the crowded Democratic field, but the surve