For a sense of what this climactic week for the 113th Congress feels like, a well-timed visit to the Capitol’s main subway platform will do the trick.  

On a quiet day, the station tucked beneath the Senate’s ceremonial steps is about as antiseptic as it gets, the dull white walls and fluorescent lighting more reminiscent of a mid-century hospital than one of the true “corridors of power” in the most powerful government on Earth. But whenever the buzzers sound and the special bulbs inside the wall clocks light up, signaling a roll call vote is underway, the room fills with a frenetic energy unmatched in any other place on the Hill that’s open to the public. And that’s rarely been truer than this week — an ending for the lame-duck session marked not only by the tensions surrounding the behemoth budget bill and the gut-wrenching Senate report on CIA excesses and deceptions , but also the bittersweet preparations for a change in partisan control and the departures of 1 out of every 8 senators.  

Whenever conditions above turn cold or rainy, the underground subway tunnels become the conduit of choice for senators hustling toward the floor from their offices or committee meetings. And while the electric train trip to the Capitol basement is a great equalizer, the moments after arrival present a powerful sorting mechanism.  

Dozens of aides, clusters of lobbyists, curious tourists and an enormous pack of ravenous reporters all know there’s no place better than the train platform to claim a moment of unscheduled face time with a United States senator. How each of them relishes, endures or avoids this rapid-fire game of catch-and-release reveals plenty about their current place in the shifting senatorial pecking order.  

Getting mobbed by the gauntlet can inflate an already considerable political ego, spur on national ambition or, at a minimum, create an unscripted moment for self-promotion. Being ignored by the crowd is a blunt reminder that power and influence are ephemeral, even for those in the most prestigious legislative positions. And avoiding the subterranean scene altogether can either be a mark of status (party leaders Harry Reid and Mitch McConnell have suites just off the floor) or an admission of despondence (Democrat Mary L. Landrieu hasn’t been spotted much since her defeat in Louisiana last weekend).  

The scene Tuesday morning was illustrative, with votes on a pair of nominees for the Tennessee Valley Authority board taking place just as the report on CIA interrogation methods was being released and details of the $1.1 trillion spending and policy package were spilling into view.  

A human wave of attention-seekers swelled around Sen. Dianne Feinstein as she emerged from the sleek computer-operated monorail car that brought her from the Hart Building. So thick was the phalanx that it totally obstructed any glimpse of her purple-wool-clad form as the California Democrat strode toward the floor to detail some of the more damning details in the torture report, which she’s been shepherding through several years of intensifying controversy as Intelligence Committee chairwoman.  

A few minutes later, a chorus of clicking camera shutters heralded the arrival of an old-fashioned tram from the Russell Building carrying Sen. John McCain of Arizona. He entered the pantheon of most quotable and press-savvy senators long before his 2008 turn as the GOP presidential nominee. But on this day, his strength as a media magnet was as powerful as ever — his standing as the incoming Armed Services chairman and his time as an abused prisoner of war in Vietnam adding to the importance of his rare (for a Republican) defense of Feinstein’s report and condemnation of the practices it detailed.  

But only one photographer (my colleague Tom Williams ) snapped off a few frames when the avuncular Sen. Saxby Chambliss of Georgia got off a subsequent trolley and sauntered up the escalator — even though, until his retirement becomes official in four weeks, he’s the ranking Republican on Feinstein’s committee.  

A throng surged toward Tennessee Sen. Bob Corker, the GOP chairman of the Foreign Relations Committee as of January, plumbing for information about when he’d launch debate on legislation authorizing a military campaign against the Islamic State terror group. The outgoing Democratic chairman, Robert Menendez of New Jersey, was penned in by a press gaggle that essentially ignored his bids to chime in.  

During his 11 months in office, Democrat John Walsh was among the most easily recognizable junior senators thanks to his brush cut and steel-rimmed glasses. But his graduate school plagiarism destroyed his shot at turning an appointment into a full term in Montana, and he’s ending his quick career as a bit of a pariah; no one at all approached as he ambled through the crowd.  

He passed within a few feet of Mike Johanns, a former Republican governor and Agriculture secretary who opted against a second Senate term in Nebraska. He was much more interested in chatting about his coming family road trip to Florida than in discussing what provisions he’d been focused on during his final days on Appropriations.  

The only person buttonholing Sen. Mark Begich, who was defeated in his first re-election try, was solely interested in who might carry the torch against federal approval of genetically modified salmon after the Alaska Democrat is gone.  

The only reporter approaching Sen. Tim Johnson, who’s retiring after four years holding the Banking Committee gavel, wanted his reaction to new Federal Reserve regulations on the biggest banks. (Upstairs, the galleries were nearly empty while Reid offered his farewell tribute to the South Dakota Democrat, focused on his determination despite a physically debilitating brain hemorrhage in 2006.)  

And the diminutive Kay Hagan, a Democrat who lasted just one term as North Carolina’s junior senator, clutched a paper coffee cup and stared into the middle distance — waiting, without anybody making conversation with her for several minutes, while a clutch of aides for other senators pressed front of her into the narrow passage that serves as the basement elevator lobby.  

Before casting one of the final votes of her tenure, she would have to wait among the staffers in a traffic jam. It was created, predictably, when one of the GOP’s “it” senators, Florida’s Marco Rubio, decided to hold court with the press before being whisked up to the floor.  

Related:

What the Landrieu Adieu Says About the 2015 Senate


Why Freshman Week Is a Lot Like College Orientation


The Almost Invisible Final Days of a Once-Forceful Leader


The 114th: CQ Roll Call’s Guide to the New Congress


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