President Biden took questions from reporters for about an hour in a news conference that showcased his strong command of foreign policy but also included the kind of verbal stumbles that have stoked concerns from members of his party about his fitness to continue his campaign. The most notable flub was calling Vice President Harris “Vice President Trump” in the session’s opening minutes. Moments after the news conference ended, Rep. Jim Himes (D-Conn.) issued a statement calling on Biden to “step away” from the race and “make way for a new generation of leaders,” joining a growing list of lawmakers who have called for Biden to step aside.