Biden’s Debate Stumble Exposes His Fragile Front-Runner Status

(Bloomberg) -- Joe Biden remains the man to beat for the Democratic presidential nomination, but the party’s first debate exposed vulnerabilities that will test the former vice president’s front-runner status as the ground shifts beneath him.Biden’s rivals on the Miami stage took aim at his age, his 36-year voting record in the Senate, and nostalgic remarks about having civil relationships with segregationist senators. The 76-year-old elder statesman benefits from a deep reserv