I'm here at a packed Joe Louis Arena in Detroit, where Governor Jennifer Granholm just introduced her two special guests: Al Gore and Barack Obama. I've attended more than my share of live sports events before. The roar was as deafening as any I've ever heard.

One interesting note: When Granholm spoke about Senator Hillary Clinton, whom she'd supported during the primaries, the crowd gave a lusty boo and kept it up for about two minutes, completely drowning out Granholm's plea for unity. (Granholm, to her credit, gave it with a smile anyway.) By contrast, when Gore just suggested John McCain was an opponent who deserved respect, the crowd gave a cheer. It was a tepid one, but a cheer all the same.

I guess Clinton supporters aren't the only ones still bitter about the primaries.

Update: During his (lengthy) remarks tonight, Obama made his own pitch for unity--taking note of the noise the crowd had made while Granholm had been speaking and then, when one audience member began booing again, singling him (or her?) out by saying "I'm talkig to you up there." Obama repeated many of the lines he'd used before, hailing Clinton for "lifting the sights of young women across America, including my daughters." He also added one I hadn't heard before, although I suspect it's not new either: "And she's tough. That's why this race took so long. She's a fighter. And we need fighters in the Democratic Party."  

--Jonathan Cohn