Watch | Obama endorses Hillary Clinton in new campaign video

President Barack Obama formally endorsed Hillary Clinton's bid for the White House on Thursday, praising his former secretary of state's experience and grit, and urging Democrats to unite behind her in the fight against Republicans in the fall. Meanwhile, Hillary Clinton's Democratic opponent, senator Bernie Sanders says he'll continue campaigning for next week's primary in Washington, DC - not yet offering to officially endorse Clinton. Obama is set to hit the campaign trail with Clinton next week as she heads to Wisconsin.