A little-known congressional maneuver could block members of the Democratic Socialists of America (DSA) from being sworn in as members of the House of Representatives next year, even if they win their elections on Tuesday.Members-elect must swear an oath to uphold the Constitution before they can become full members of the House. At the beginning of a new Congress, that oath is typically taken en masse by all 435 members, led by the House speaker.But an argument circulating in conservative circles posits that any member-elect can challenge another member-elect's right to be sworn in, provided...