JARRETT RENSHAW and MICHAEL MARTINA SUPPORTERS  of Joe Biden danced in the streets outside a ballot-counting centre in Philadelphia as the steadily growing vote tallies showed the Democratic former vice president could soon be declared the winner of the U.S. presidential election. In Detroit, several hundred supporters of President Donald Trump, some visibly armed with guns, raised premature chants of "We won!" outside a counting center, despite it looking increasingly unlikely that this would prove true. Philadelphia appeared to relish its turn as the center of the nation's attention, even if it was earned only by the relative slowness of…