RICHMOND, Va. — The political tumult in Virginia widened Thursday as the State Senate’s top Republican faced an onslaught of questions about racist photographs and slurs in a college yearbook that he helped oversee, transforming the Capitol’s nearly week-old crisis into a bipartisan reckoning over personal conduct. The senator, Thomas K. Norment Jr., who is the majority leader, was the managing editor of the 1968 Virginia Military Institute yearbook, which included images of students in blackface.