clinton support slipping as sanders surges in iowa and new hampshire. sanders suddenly sharing a stage with the front-runner. >> feeling good about the poll and the support we are getting here today. >> reporter: then the wild card of vice president, joe biden. >> i hope you run, man. i hope you run. >> hey, guys. >> reporter: his labor day visit to pittsburgh had the look and feel of a campaign event, with residents urging biden to jump in. striking passionate tone addressing union members in a fiery sweech. >> i'm mad, i'm angry. when the middle class do well, the wealthy do well and the poor have a way up. organize, organize, organize. >> reporter: he was enjoy thag moment as he inches closer to making a decision. until then, this race is in a holding pattern.