The inside story of how the U.S. Capitol gets ready for the State of the Union

It may only draw half the viewers it once did, but for staffers at the U.S. Capitol, Tuesday night’s annual State of the Union address by the president is their Super Bowl. It is the single most complex logistical undertaking held each year at the United States’ more than 200-year-old central legislative building. Heroic efforts and months of work by press gallery staff, the House and Senate sergeants-at-arms and Capitol Police are required to stage the event for television cameras around the world.

On Monday morning, while the rest of the federal government was closed for Martin Luther King Jr. Day, staffers, photographers and cameramen took part in one of the final acts of State of the Union staging, a private hourlong rehearsal of the speech’s rites and rituals in the House chamber. The 11 a.m. Monday dry run for the 9 p.m. Tuesday speech is conducted annually to prepare for television timing, placement for photographers and cues for the sergeant-at-arms staffers who keep the pomp and circumstance of the speech going, from announcing the president when he arrives at the House doors to keeping order in the packed chamber while he speaks. The House’s central aisle is so narrow and so crowded with dignitaries during the speech that the small number of photographers assigned to take pictures from the floor must carefully choreograph their movements on Monday, walking the tight space forwards and backwards, so that they do not bump into each other on Tuesday.

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The timed practice was especially important Monday because one of the two sergeants-at-arms, the Senate’s Frank Larkin, is only two weeks into the job and coordinating his first State of the Union address.

When Americans turn on their TVs and computers to watch President Barack Obama outline his vision for the country, the images and stories they will see also will reflect the weeks of work by multiple professional press gallery staffs inside the Capitol, who plan the event to accommodate hundreds of journalists, guests and dignitaries. Outside the building, the Capitol Police shut down the areas around the Capitol, which is usually open to the public, at 6 p.m. Only credentialed or authorized staff members are allowed on much of the Capitol complex after that time. Roads around the Capitol close to vehicular traffic at 7 p.m. in preparation for the president’s arrival. Public tours of the building, which usually run until 4:30 p.m., stop that day at noon.

“I always liken the State of the Union to our equivalent of the Super Bowl,” said Olga Ramirez Kornacki, director of the House Radio TV Gallery. On the occasions that she has given walk-throughs of the night’s many media locations to groups that have never seen a State of the Union before, she said, “They were just astounded. They did not have an idea of how many people are involved and how big it is.”

Unlike the real Super Bowl, viewership of the State of the Union is declining, with approximately 20 million fewer Americans watching Obama’s 2014 address than tuned in for his first speech in 2009. But the sheer number of reporters who cover the event is still staggering.

Yahoo News interviewed staff at the four major news galleries in the Capitol — Daily Press, Periodical Press, Radio TV and Photographers — to paint a fuller picture of how a State of the Union address gets transmitted from Washington, D.C., into the homes of millions of Americans across the country. Our location-by-location breakdown:

Statuary Hall. The heart of the night’s festivities is a place called Statuary Hall, a marble chamber just yards from the House floor in the Capitol. Divided into 24 segments assigned to 30 different media organizations, from above it looks like an overstuffed media pie. Approximately 125 people in broadcast media, from technicians to radio producers, use the amphitheater-shaped chamber as their studio for the evening.

The Cannon Rotunda. Located in the House office building adjacent to the Capitol, 21 media organizations broadcast from inside the Cannon Rotunda, and two news organizations plan to broadcast live with anchors from the exterior balconies to the Cannon space, which have great views of the Capitol dome, now under reconstruction. The 21 positions in the Cannon Rotunda are also used as “react locations” later in the night for elected officials who do live shots with the networks. The Radio TV Gallery estimates that 50 broadcast media personnel are required to staff just the cameras in this one room.

The Russell Rotunda. Located in a Senate office building adjacent to the Capitol, the Senate Radio TV gallery assigns 24 positions on the inside and outside balconies for the evening, involving another approximately 80 broadcast professionals.

The Capitol grounds. Six to 10 cameras are assigned to locations outside the Capitol building, open spaces on its East Front known as the House Triangle and “the Elm Tree” (near the picturesque tree in question), to get so-called “beauty shots” of the building’s exterior, as well as B-roll of arrivals to the building that network anchors can comment on later as they broadcast live in the run-up to the speech.

Inside the House chamber. Broadcast groups are assigned 10 camera positions in a specific gallery  overlooking the House floor, Gallery 11, to shoot the event. Also stationed in Gallery 11 is the network responsible for the pool feed (camera footage taken by one organization and shared with all other credentialed outlets), which sets up an additional nine cameras. This year, the broadcast pool network is Fox News, which worked over the weekend to set up its feed and will have 44 staffers in the building and in broadcast trucks working to cover the event.

The Daily Press Gallery assigns 90 seats within the chamber in the overhead spectator galleries for reporters who work for newspapers and wire agencies that produce reported content every day. The Periodical Press Gallery reserves an additional nine seats for specialized Hill publications and magazines.

The Print Photographers Gallery has 17 permanent photojournalists and 15 rotating photographers who cover the event, in addition to the one designated photographer who takes pool pictures from the floor.

The House Recording Studio, an organization that provides radio and television recording services for members and provides regular feed of the floor, operates two robotic cameras for the State of the Union that also feed coverage to the networks.

And finally, there is the team on the House floor, where the 535 members of Congress will assemble with the justices of the Supreme Court to be addressed by the president, who will stand before them flanked by the vice president and the House Speaker, Republican John Boehner.

Tuesday night, five photographers will cover the speech from the House aisle, including a print media photojournalist, an official House photographer, an official Senate photographer, a White House photographer, and a cameraman from Fox News, the broadcast organization responsible for televising the speech. This year, the designated news photojournalist is Mandel Ngan of Agence France-Presse.

Underneath the Capitol Rotunda. In a windowless room known as “The Crypt,” the Radio TV gallery works with the Architect of the Capitol to install a half-dozen televisions so that aides to senators and representatives can watch the speech before staffing their bosses upstairs when they grant interviews to reporters. More than 100 staffers also will get maps of Statuary Hall, showing which TV networks are located where, as well as a walk-through of the space hours before the speech.

This year, because a sitting member of Congress, Sen. Joni Ernst of Iowa, will deliver the official Republican reaction to the State of the Union, more work and accommodations must be planned to ensure that broadcast goes off smoothly. According to Ramirez Kornacki, 20 broadcast technicians will usually work from a separate truck to coordinate the reaction coverage for whichever news group is assigned the opposing party's response.

One of the little-known rules regarding the response is the formality of its timing. Once the president leaves through the doors of the House chamber — not when his speech is finished or as he’s glad-handing on the floor — a hard clock begins. Once the clock starts, the Republican lawmaker delivering the speech must wait five minutes until after the president’s exit before he or she can begin the GOP address.

A pool still photographer will also be present, taking pictures at a time designated either before or after, but usually not during, the Republican lawmaker’s address.

On a night where both parties will look to use the media to score quick political points, the nonpartisan press gallery staffs who do the groundwork to ensure the night runs smoothly view their jobs not as a politicized endeavor but as a public service.

“In the end, it’s the number of interviews that get to be done that is our measure of success,” Ramirez Kornacki said.