DENVER: When most people think of Joe Biden, they think Senate longevity, confidence, a liberal with a free-wheeling impulse to give you his never-to-be-humble opinion. What they don't think of is a man who could have a great impact in Pennsylvania. The question becomes: Can he make his impact as broad as Hillary Clinton -- another Scranton native -- did in the Pennsylvania primaries? Hillary glowed in Pennsylvania. She made Pennsylvania her second home and it stuck with voters. John Kerry, married to the Heinz ketchup heiress Teresa, did the same thing in his runup to the 2004 election. He...