(Reuters) - Former President Barack Obama, back on the campaign trail on Thursday for the first time since he left the White House, called on voters to reject a growing “politics of division” that he said was corroding American democracy. Without mentioning Republican President Donald Trump by name, Obama told campaign rallies in New Jersey and Virginia that voters could send a powerful message about the type of politics they want by backing Democrats in Nov. 7 elections in the two states. “What we can’t have is the same old politics of division that we have seen so many times...