I've done a brief remembrance of John Edwards's campaign for The Guardian. A taste:
It's widely noted that there's no enormous policy gap between Hillary Clinton and Barack Obama. Less widely noted is that it didn't always have to be that way. Both Clinton and Obama are running on domestic platforms that are much, much, much more ambitious than anything Al Gore or John Kerry put on the table. And not because Kerry was a notably right-wing Democrat or Clinton a from-the-left insurgent. Rather, the centre of gravity within the party shifted several notches left between the last cycle and this one. In part, that was a response to shifting dynamics in the real world. But to a surprising extent, it was simply a response to John Edwards.
Something I don't get into in the piece is the extraordinarily vigorous efforts of Edwards-supporting blog commenters -- most notably Petey. As the months went by, I came to think increasingly well of Edwards, and those commenters along with the work of Edwards' formal online communications team made a big difference. Beyond that, what Jon Cohn said.