DES MOINES, Iowa -- As stump speeches become as polished as a high-gloss redwood coffee table, campaign reporters learn to listen for the cue to file their stories, pack up their electronic gear, and head for the press van. Often the candidate utters a tell-tale phrase that telegraphs that he is rapidly winding down. The most famous of these rhetorical tics was Nelson Rockefeller's slavish dedication to a particular vague, uplifting phrase during his 1964 presidential campaign: "the brotherhood of man under the fatherhood of God." This quickly became known by the acronym BOMFOG -- and during that Olivetti-era campaign, the line prompted reporters to head for the bus they were boys on.

For Barack Obama, a candidate who once struggled with the endings of his speeches, the exit-strategy signal is a reference to a place: Greenwood, S.C., a town in the northwestern corner of the state. What follows is a shaggy-dog story of varying length that always contains these three essential elements:

1). Obama won the endorsement of a South Carolina state legislator by impetuously promising to visit her hometown of Greenwood.

2). Obama reluctantly made the 90-minute trip to Greenwood.

3). In Greenwood, Obama encountered a longtime member of the City Council whose political trademark was incessantly shouting, "Fired up! Ready to go!"

Needless to say, this raw narrative material would not provide kindling for a story-telling session around a camp fire. Nor does the tale provide an obvious moral, other than to never make rash promises -- even in politics -- that you do not want to fulfill. But somehow Shecky Obama has turned this seemingly prosaic story into a self-deprecating standup riff. It's not exactly Friars Club material, but it is good enough for amateur night say, at a club called the "Mike and Stool" or the "Laugh Riot."

Each time I hear Obama's "Fired up!" story, it gets longer. The version Obama told Sunday afternoon in Cedar Falls, Iowa, clocked in at over six minutes. That is roughly as much time as Chris Dodd got to speak in the last debate. When reporters now hear the words "Greenwood, S.C.," they know they have enough time for a bathroom visit, a hush-hush cellphone call with a confidential source, 17 voter interviews and a sandwich.

Here is how Obama stretched it out in Cedar Falls:

The opening: "I just want to tell you this story, some of my supporters may have already heard this story, but it's a good story, so I'll just tell it anyway."

Grade: D-. Never apologize for your material. That is like Dave Letterman being reluctant to give his Top 10 List because the band already heard it during rehearsal.

The promise: "I must have had a glass of wine with dinner because I said, "OK ... only to learn that Greenwood is an hour and half from anyplace else. It's remote."

Grade: B-. Obama wins regular-guy points for suggesting that he might have been tipsy when he pledged to go to Greenwood.

The night before: "It's midnight. I've been campaigning for 10 days straight. I'm missing my kids, I haven't seen my wife ... The next morning, I wake up and I feel worse than I did the night before when I went to bed. You have those nights, huh?"

Grade: A. Obama takes Rudy Giuliani-style self-pity over the rigors of running for president and repackages it in a way that could appeal to any traveling salesman doomed to stay in motels so bad they steal your soap. No other candidate in modern political history could have pulled off the "You have those nights, huh?" line without sounding patronizing.

The trip: "It's pouring out. It's a miserable day. And there's a bad story in the New York Times ... I go downstairs. My umbrella broke and I'm soaked before I get into the car. I'm wet, I'm mad and I'm sleepy."

Grade: A-. As Obama tells it, you can feel the rain and even the pain over the New York Times.

The encounter: "There's this little woman ... maybe 5-2, 5-3, about 65, dressed like she's going to church with a big church hat ... It turns out that this is a city councilwoman from Greenwood, who is famous for her chants ... So for the next five minutes, she just keeps on chanting ... 'Fired up! Ready to go!' ... And I'm standing there and I'm completely upstaged."

Grade: B+. Obama gets scene-setting credit for the "big church hat" image.

The conversion: "So I join the chant and it makes me feel good ... And for the rest of the day, even after I left Greenwood, I talked to myself and I said, 'Are you fired up? I'm fired up. Are you ready to go? I'm ready to go.'"

Grade: B. In a campaign cycle in which his rivals will latch on to anything, Obama is taking a risk in admitting, even in jest, that he talks to himself.

The takeaway: "So it goes to show you how one voice can change a room. And if you can change a room, you can change a city. And if you can change a state, you can change a nation. One voice can change the world."

Grade B+. It all seems like a rhetorical stretch to me, but crowds in Iowa applaud lustily as Obama goes into his closing refrain. And in show business, it is not the snarky reviews of the critics but the reaction of the audience that counts.

If Obama can do this much with a chanting South Carolina city councilwoman, I would love to see how he would personalize the filthy, low-life, vaudeville-era, movie-inspiring joke known as "The Artistocrats."