Convention bets hard on hope Kamala pick will provide left-wing cover for sharp messaging return to the center. Vice President Joe Biden wrapped up the Democratic Convention Thursday night, putting an authentic and well-received closing argument at the end of an otherwise halting, depressing and frankly alien four-day rally, and previewing what may be the campaign’s calculation that a Kamala Harris VP provides left-wing cover for a rapid return to messaging from the Democratic Party’s political center. Biden used the 25-minute speech, delivered from an empty convention center in Wilmington, Delaware, to contrast President Donald Trump’s “darkness” with his own...