As a pre-Chanukah present for political junkies, NPR is hosting an early afternoon Democratic debate today (2 p.m. Eastern time), the next to last face-off before the Jan. 3 Iowa caucuses. There is a wonderful Al Smith-era retro quality to staring at a radio dial for two hours and -- an even bigger bonus -- Anderson Cooper and CNN will not be in charge of the questions.

At a time when political reporters should demand hazard pay to check their e-mail (too many stinging press release attacks by Hillary Clinton and Barack Obama), a radio debate brings with it intriguing challenges. With no visible smiles to soften the blow, even the mildest critiques of other candidates risk sounding mean and strident. And natural radio voices give an edge to two candidates -- Obama, who can easily adopt the tone of a late-night jazz host on public radio, and Chris Dodd, whose deep resonant sound would have been tailor-made for selling Maxwell House coffee during the commercial breaks on, say, "The Fred Allen Show."

Today's debate may also mark the return of a familiar figure, John Edwards playing the Nice-Guy Candidate. This was Edwards' self-assigned role during the run-up to the 2004 caucuses, and it served him well as he surged from the back of the pack (and, trust me, Bill Richardson and Joe Biden remember) to finish a close second to John Kerry. There is no happier place in a multicandidate political race than to be smiling on the sidelines as your principal rivals chew one another up. Despite his aggressively populist rhetoric this time around, Edward still retains some of the glow from that 2004 halo in Iowa. In the Des Moines Register poll released this week, 26 percent of likely caucusgoers consider Edwards to be the most likable Democrat. That puts him behind Obama in that smile-button contest but way ahead of Clinton (14 percent).

A final pre-debate thought: Joe Biden deserves credit for having been the least panicked Democrat about Iran's purported headlong rush to become a nuclear power. In an interview with me two weeks ago (before the alarmist intelligence estimate about Iran was publicly scaled down), Biden stressed that the real nuclear risk zone is Pakistan, which currently has the capacity to reach the Middle East with a missile. Now, with a little hindsight, the interview transcript may be worth rereading, especially if you cannot endure the white-knuckle tension of waiting for the NPR debate to begin.