See Slate's complete Democratic Convention coverage.
Barack Obama and Joe Biden became running mates five days ago, but it wasn't until Wednesday night that they became a ticket. There was the official nominating procedure, of course, but there was also a spiritual hurdle: moving past the Clintons.
Hillary Clinton did her part Tuesday night, making a full-throated pitch to her supporters, and then on Wednesday Bill Clinton did his. He praised Obama relentlessly and took care of the one omission from his wife's performance the night before: Calling on his experience during eight years in the White House, Clinton vouched that Obama was ready to be commander in chief. The only way he could have endorsed Obama more enthusiastically is if he'd kissed him.
After Clinton, there wasn't much oxygen in the room for Joe Biden. But he didn't need to deliver the most beautiful speech. That's not his job. His job is to use his quirky approachability to introduce Obama to voters who have been skeptical about him. A guy named Barack needs a guy named Joe as his running mate. (In political-speak, they call this being the validator.)
Biden's best pitch came not on the issue of foreign affairs, Biden's strong suit. It came shortly after he began, when he offered a little collage of kitchen-table conversations about families facing hard times. "Should Mom move in with us now that Dad is gone? Fifty dollars, $60, $70 to fill up the gas tank? How in God's name, with winter coming, how are we going to heat the home?" Working-class and Catholic voters may identify with a guy who drops the expressions of their faith or tells gritty stories about how Catherine Eugenia Finnegan Biden taught him how to defend himself. (In case you didn't notice, she's Irish.) If they identify with Biden, they might listen to him—and that's the first step in overcoming their doubts about the man at the top of the ticket.
It's not an easy task. Blue-collar voters in Delaware may like Biden when he's selling himself, but will his sales pitch work elsewhere for Obama? Can he really be an ambassador to the food court when he looks like an ambassador to the Court of Saint James'?
It's not the only contradiction. Biden talked at length about change in Washington, but with the tailored suit and leonine hair, he looks as much a Senate institution as the bean soup. Biden said Obama was ready to be commander in chief, but there are plenty of times when he's said the opposite. "I think he can be ready, but right now I don't believe he is," he said during the primary. "It's awful hard, with only a little bit of experience to have a clear sense of what you would do on the most critical issues facing us today."
Biden's assertions about Obama's foreign-policy judgment may or may not stick. But he's got a much better chance of fulfilling the traditional attack role. He was all over John McCain Wednesday night—and will be for the rest of the race. He has perfected the senatorial two-step of lathering his victim in friendship first ("John McCain is my friend") before dismantling him repeatedly. That lends weight to the attacks, and Biden knows his brief when talking about foreign affairs.
The evening ended with another of the compulsory convention exercises: the candidate's "surprise visit." Obama arrived onstage to hug his running mate and hand out the praise. First he paid tribute to his wife (whose tears upon hearing Biden's life story should be in a campaign commercial), then he honored Hillary Clinton. Finally, he praised Bill Clinton. The mantle had been passed from one generation of Democrats to the next, and, safely in his position as the new leader, Obama was in a position to apply the benedictions.