U.S. Senate Chamber, ca. 1873. National Journal

In politics, there's little daylight to be found between John McCain and Lindsey Graham, a pair of defense hawks who see eye to eye on just about every issue. But this session, the pair got even closer, at least in terms of where they sit on the Senate floor: They're finally desk neighbors.

McCain made the move, grabbing the spot next to Graham when it opened up before the 114th congressional session. Prior to that, he was just one row ahead of the senator from South Carolina, but that was one row too far. (Graham joked that with McCain's arrival, "the neighborhood really went to hell.")

So it goes on the Senate floor. Easy as it is to forget amid the high-profile wheeling and dealing, the Senate floor is still a work space, and like any work space, where (and with whom) one sits is not a matter to be taken lightly. And so, when desks get reshuffled at the start of each session, senators mull, confer, and strategize in a bid to snag the exact spot they want.

"I remember being utterly confused," said Sen. Jeff Sessions, who took office in 1997. "I had my staff, and I said, 'Let's pick a good spot,' and we went round in circles."

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After the election, Republicans and Democrats allow their most senior members first choice of the open desks and then work their way down the seniority line.

Sen. Orrin Hatch has inherited the right to sit where he pleases. The longest-serving Republican senator has chosen a spot directly behind Senate Majority Leader Mitch McConnell, an aisle seat in the middle of the action. During a late Thursday session in March—a day filled with a rapid succession of amendment votes—Hatch could be found calmly seated, reading glasses on, his fingers skimming the words to a book detailing the establishment of the postwar world's monetary system. It's a spot where he can multitask while remaining in the center of the chamber's floor.

"I'm closer to the aisle, which I've always tried to be so that you can get recognition," the Utah Republican said. "In a very serious situation, sometimes getting recognition is the difference between winning and losing."

Next to him is Sen. Thad Cochran, who joined the Senate just two years after Hatch in 1979. The pair of veterans, along with Sen. Richard Shelby, make up the three-person row behind Republican leadership and near the presiding officer. And that's how Cochran likes it.

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But sometimes, the pull of the neighborhood keeps a senator in a seat with a dismal vantage point. Take Sen. Chris Murphy: front row, end seat in the Democratic section farthest from the center. From the press area, a reporter has to stand up and peer over the railing to see the Connecticut Democrat—if he's there.

"Most of the time I actually sit at Brian's desk," Murphy said, referring to Sen. Brian Schatz of Hawaii, "because you can't see anything from my desk, so often Brian has to kick me out of sitting in his seat."

He had the chance to move—but, likely, that would have meant leaving behind his row-mates, Schatz and Sen. Kirsten Gillibrand. "They're both friends, and during these long vote sessions, it's kind of nice to be sitting next to friends," Murphy said.

That doesn't mean he always physically sits during votes, as many senators don't. They usually dart around the floor, in and out of the cloakroom, to and from leadership. The desks, though, can make comparing notes just that much easier.

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Two Senate delegations sit next to each other. For the Tennessee senators, it was a happy coincidence. For the Idaho senators, it was on purpose.

Sens. Bob Corker and Lamar Alexander sit in the farthest section on the Republican side from the center of the chamber. Alexander has the aisle seat. Corker sits to his right.

"I think we both just like sitting down on that row," Corker said. "A lot of people don't like it because of the angle that the cameras are. I know numbers of people have moved from that situation, and they'd rather be out in the middle. "¦ I think we both like sitting there; it's an easy place to sit and talk with other people when things are going on, but for me, certainly, being beside someone I think so much of is a plus."

Becoming neighbors was a coordinated affair for longtime colleagues James Risch and Mike Crapo.

"Mike and I are very, very close," Risch said. When Risch was running the Idaho Senate, Crapo was on his leadership team, Risch said. Crapo was elected to the U.S. Senate with Risch following a decade later. And, now, they're also together on the Senate floor.

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"We're closer than probably any delegation here," Risch said. "If you look at our voting records, we vote together 99.9 percent of the time, always check with each other before we vote. Sometimes, one will disagree with the other, and we hash it out and usually yield to the person that feels the strongest about it or has the best arguments on it, but we almost always are able to reconcile with the differences."

Once senators have analyzed the floor and selected from the open spots, there's another decision: What actual desk do they want?

The congressional desks have seen seven different numbering systems, with the current one beginning in 1957. The evidence of a desk's history can be found inside the desk drawers, where some senators began inscribing their names in the early 1900s, a tradition that still lives on today. (Late one night, during a lengthy vote-a-rama, Alexander scribbled his name with, as he recalls, a paper clip.)

And some senators choose their desks based on history.

Sen. Susan Collins of Maine wanted the desk of former Sen. Margaret Chase Smith, who also represented Maine, for her own. "She was a real inspiration to me when I was growing up," Collins said. "She was the only woman serving in the Senate for many years, so I'm very honored to sit at her desk."

Alexander also wanted the desk of a predecessor from his home state—former Sen. Howard Baker of Tennessee—because he used to serve on Baker's staff.

And Sen. Amy Klobuchar wanted the desk of another Minnesotan, former Sen. Hubert Humphrey. She received Humphrey's desk—but it actually had belonged to Gordon Humphrey, a Republican from New Hampshire. She occupied the seat for the first two years of her term, and then swapped it for the right Humphrey.

But as a long night wears on, there's one desk particularly critical to keeping the Senate running: That's the one used by Sen. Pat Toomey, a Pennsylvania Republican. Tucked inside his desk is a spread of candy and chocolate from his home state. When asked if the rumblings were true, if he was the senator with the candy, he responded, "I am the candy supplier."

It's a tradition. An aisle seat on the back row of the Republican side—adjacent to the chamber doors where many senators flit in and out—is the candy desk. It's a commitment Toomey readily accepted.

"Since Pennsylvania is the No. 1 candy maker in the country, I took the desk," he said. "And I keep it stocked."

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