PHILADELPHIA (AP) – Officials from six states and the District of Columbia have asked a federal judge to halt what they say are slowdowns at the U.S. Postal Service that threaten the upcoming presidential election. They argued Thursday in U.S. District Court in Philadelphia that on-time delivery dropped sharply in July and has not fully rebounded as the nation battles a pandemic and prepares for an election that could hinge on mail-in ballots. Judges in Washington state and New York issued emergency orders this month in similar cases. The states involved in Thursday’s hearing are Pennsylvania, California, Delaware, Maine, Massachusetts and North Carolina.