Elizabeth Warren, the 2020 Democratic presidential candidate, hit the campaign trail for the first time on Sunday hoping to shake off criticisms of her questionable past claim to Native American heritage that could undermine her White House bid. The Massachusetts senator, regarded as a top tier contender for the nomination but facing an increasingly crowded Democratic field, immediately took aim at Donald Trump, who she said could be in jail come election day. "By the time we get to 2020, Donald Trump may not even be president," Ms Warren said. "In fact, he may not even be a free person." Ms Warren, 69, travelled to the critical electoral state of Iowa less than 24 hours after officially launching her candidacy. In Cedar Rapids, she spoke of rebuilding the middle class through economic equality and challenging corporate wrongdoing. "I want to be clear on this. I’m not taking one thin dime of PAC money. I’m not taking one thin dime of federal lobbyist money. And...