By Ezra
As addendum to my Don't Draft Krugman argument below, it's worth saying that, contrary to the energy we put into senate races, individual senators can really do remarkably little. Think of last cycle's great hopes -- Ken Salazar and Barack Obama. Heard from either lately? The most waves Obama's made have been in the form of a recent rebuke to the blogosphere! And as for the powerhouses? Kennedy, Clinton, and so forth? The closest you get to a recent accomplishment there is Kennedy's cosponsorship of No Child Left Behind.
The US Senate is a numbers game. If you have more guys than the other team, you can do a fair amount. If not, it really doesn't matter how many brilliant minds populate your side, they're going to be powerless. And then, when you regain control, those brilliant minds still find their awesome intellects subordinate to the leadership team's agenda and the President's priorities. Indeed, the only place where individual senators make a difference is in election cycles and, potentially, as future presidential candidates, although we well know that they've tallied up a rather lackluster record there during the past 50 years.
The real fight is in establishing the conditions for majority control, which is to say working the media, disseminating your ideas, pushing better flacks on the shows, expanding your base, building coalitions, funding good candidates, choosing races wisely, and generally creating an atmosphere where voters elect Democrats rather than Republicans. A guy like Krugman is better utilized as part of that operation than as another well-known, little-seen, and wholly impotent senator.