Official From Pawnee, Ind., Buttonholes Senators

Leslie’s gray power suit was appropriate for the occasion, but the cherry-red Keds gave the game away. This was Amy Poehler, who once memorably played Hillary Rodham Clinton on “Saturday Night Live” and who now plays Leslie, who worships Mrs. Clinton, on the NBC comedy “Parks and Recreation,” shooting a scene on location: a balcony on the ninth floor of the elegant Hay-Adams Hotel. (The camera frame made sure not to include her footwear.)

The cast and crew of “Parks and Recreation” had come to Washington and its sweltering July heat for the glorious location shots and, more important, its senators. Barbara Boxer, Olympia Snowe and John McCain were on the way to take part in an episode set in Washington — “as long as Afghanistan doesn’t invade Kyrgyzstan,” said Michael Schur, the executive producer who runs “Parks and Recreation.” “We just found out they already had a vote today, so we’re just hoping they can actually take a break and show up.”

Nobody was anticipating the guest stars more than Ms. Poehler, who said she hoped Mr. McCain would remember “the time we shot a scene in the shower together.” That was on “SNL,” when Mr. McCain hosted the show in 2002. It hardly seemed like a moment anyone would be likely to forget, but Ms. Poehler said, “It’s all a beautiful, hazy blur what happened in there.”

She punctuated the remark with one of her signature high-pitched, two-note cackles. Ms. Poehler and her cast mates Adam Scott, who plays Leslie’s boyfriend, Ben; Chris Pratt, the dim but irrepressible Andy; and Aubrey Plaza, his inscrutable, socially subversive wife, April, were clearly having fun. It was their first real chance to escape the Hollywood sound stage that usually stands in for the fictional Pawnee, Ind., where Leslie is an ingenuous but ever hopeful small-time politician. But there were impediments to full enjoyment of the experience. First, the heat. Then Ms. Poehler’s aching feet. That accounted for the Keds. When she was forced to slip into black heels for other scenes, a makeup aide first covered her blisters in Band-Aids.

And it was Emmy-nomination day. The news that morning was disappointing. Though Ms. Poehler and Mr. Schur received nominations for writing, they had hoped that “Parks and Recreation” would also make the shortlist for television’s best comedy. It didn’t.

“That might have really helped us,” Mr. Schur said, noting that marginal ratings for “Parks and Recreation” have left it “permanently on the bubble.” (Last season an average of 3.5 million viewers tuned in each Thursday, which gave it an overall ranking of 152nd in terms of initial viewers.) To win another sliver of recognition might have made some difference next year at renewal time.

Squeezed into her heels, Ms. Poehler rehearsed a scene with Mr. Scott and two stand-ins playing Senator Boxer and Senator Snowe. The premise of the episode is that Ben has gotten a job in Washington with a congressman, and Leslie begins to feel that she is insignificant to the functioning of American democracy. By the time she is introduced to the two senators, she has totally lost her self-confidence.

The actors had the scene down by the time the two officials arrived, both wearing suits in shades of blue. Ms. Boxer and Ms. Snowe, who have known each other for three decades, each had a couple of lines.

The scene went smoothly. Both senators delivered their lines flawlessly, allowing Ms. Poehler to land the jokes.

Afterward Ms. Boxer, a Democrat who represents Hollywood (among other California communities), related her experiences in playing a version of her senatorial self: in the film “Traffic,” in Larry David’s series “Curb Your Enthusiasm,” in the old sitcom “Murphy Brown” and in the comedy-drama series “Gilmore Girls.”

She approved of ”Parks and Recreation.” “It’s a cute show,” she said, “and it’s related to my work — a little bit.”

For Ms. Snowe, whose constituency is in Maine, the guest shot represented her first foray into acting — unless you count the time she had to fake her way through her speech at the 1992 Republican National Convention because air jets designed to cool the speaker were placed too high and fogged up her contacts, rendering the prompter a useless blur.

But she didn’t see that much difference between political performance and entertainment performance: “I said to Barbara, ‘It’s from one theater to another.’ ”

The senators’ scene finished, all that remained was what the cast and crew clearly viewed as the day’s main event: John McCain’s arrival. That riveted even the corps of extras milling around the ersatz green room.

He made straight for Ms. Poehler. His first words to her: “Do you remember when we shared a shower together?” That elicited another cackle of delight.

In Mr. McCain’s scene he tries to get his coat from a coat room as a disconsolate Leslie keeps her back to him, not recognizing the former Republican presidential nominee. Mr. Schur had said he knew Mr. McCain had a good comedic sense but worried about his reputation for wanting to shoot only one scene or two.

“Parks and Recreation” got four takes out of him. “He’s a pro,” Mr. Schur said.

Later Mr. McCain answered coolly when asked why he accepted the cameo. “Because they asked me,” he said. “It’s one of my favorite shows.” He also suggested that it was “very popular,” which was accurate only when talking about critics.

He did offer up a theory about the similarities between politics and acting, saying, “You’ve got to have a reliable routine.”

The day went so well that Mr. Schur began considering a rescheduling of the episode. NBC had announced it would be the second of the new season, set for Sept 27.

“I don’t know,” Mr. Schur said. “This may feel so special we’ll have to use it as the season premiere.”