Democratic Senator Elizabeth Warren made her bid for the White House official on Saturday in the working-class Massachusetts city of Lawrence. <br /> <br />Warren delivered a populist call for change at her presidential kickoff, decrying a "middle-class squeeze" that has left Americans crunched with "too little accountability for the rich, too little opportunity for everyone else". <br /> <br />She and her backers hope that message can distinguish her in a crowded Democratic field and help her move past the controversy surrounding her past claims to Native American heritage.
