Indeed, Obama’s campaign had a particularly capable opposition research shop, a source of tips to many reporters, not all of them on policy. And Plouffe, in passing, outs the campaign as the source of a brief item I did in April 2007 off an Edwards campaign expenditure — probably driving as much traffic, chatter and grief as anything that short I’ve ever written.

“We did much less of this [opposition research] than other campaigns did,” Plouffe writes a bit self-servingly, “but there were times we indulged — it was our researchers who found John Edwards’s infamous $400 hair cut expenditures.”