If you want to know where all the power is concentrated in Washington, start with a building on 17th Street, not far from the White House.

Here at the Corcoran Gallery of Art is power in all its forms: political, religious, artistic and social.

This gathering of the famous and the infamous is part of

the Corcoran’s latest exhibition: “Richard Avedon: Portraits of Power.”

The exhibition of 230 photographs, which opens Saturday, features dozens of Washington’s premier figureheads, from former Speaker Tip O’Neill (D-Mass.) to then-CIA Director George H.W. Bush. The late Avedon, who began his career as a fashion photographer in the 1950s and 1960s, and later became a socially and politically aware artist, captured the images of the high profile and the lesser known. No matter the status, from the regal first lady Jacqueline Kennedy to the rumpled strategist James Carville, nearly all of Avedon’s subjects were shot in black-and-white, against the crisp backdrop of a white sheet.

The vast exhibition takes up the Corcoran’s entire second floor and spans nearly six decades of Avedon’s work, from his earlier years at Harper’s Bazaar in the 1950s to his final project in 2004 for the New Yorker (the year Avedon died). Museum curator Paul Roth said the museum chose to focus on power because power was as much a subject of Avedon’s work as the people he was actually photographing.

“He really made power and politics a center of his work,” Roth said. “He was a person who was always aware of what was going on, [and] he chose to record a particular person at a particular moment in their life.”

And at this particular moment, 54 days before Election Day, the Corcoran’s ode to power is a timely one.

“It seemed appropriate to time this between the convention and inauguration,” Roth said of the exhibit’s timing, which runs from Saturday until Jan. 25, 2009. “Thinking about Washington and thinking about the election, it all came together.”

The diverse portraits depict the stoic faces of those at the height of power, such as President Gerald Ford, and those on the cusp of it, like President-elect John F. Kennedy, photographed Jan. 3, 1961, two weeks before his inauguration. Some of Avedon’s subjects came to power through the ability of their brains, such as former Secretary of State Henry Kissinger and renowned pediatrician Dr. Benjamin Spock, while others ascended through brawn, like prizefighter Joe Louis and California Gov. Arnold Schwarzenegger.

And in a town dictated by elections, elements of politicking pepper the Corcoran’s display. A young-looking Rudy Giuliani strikes a handshake-ready pose in a photograph taken during his 1993 mayoral campaign. Republican political adviser Karl Rove playfully smirks at the camera just two months before Election Day in 2004. Just a few feet away, the eccentric Carville looks ready for an electoral fight, sleeves rolled up and fists clenched.

Avedon “recorded a particular person at a particular moment in their life,” Roth said. “He took an instant of time and made a moment of it.”

While the moment is recorded in the photograph, the meaning can change.

A dark-haired and handsome Sen. Edward Kennedy (D-Mass.) looks youthful and strong in his photograph from 1976, when he was 44 and aiming for greater heights in his political career.

“Right now looking at the picture seems very different,” Roth said, noting the 76-year-old Senator’s brain cancer diagnosis. “A photo’s meaning can change.”

The element of time is another feature of the Corcoran’s power-focused exhibition. The photographs are organized into periods of Avedon’s work, beginning with his years at Harper’s Bazaar. The exhibit moves to the civil rights era of the early 1960s, with photographs of Malcolm X and Student Nonviolent Coordinating Committee founder Julian Bond, followed by the anti-war movement of the later 1960s and early 1970s. Avedon’s 1971 trip to Vietnam is displayed in an emotional array of shots depicting both a proud and decorated Army soldier and a mangled napalm victim.

Avedon’s renowned work “The Family,” commissioned in 1976 by Rolling Stone, is included in the Corcoran’s attraction. The impressive group of 69 photographs shows a range of commanding figures that includes one sitting president, two future presidents and two first ladies, union leaders, Cabinet members, liberal activists, conservative advocates, a host of Members of Congress and a few artists. Shown on a single wall and organized in a grid, the display is one of the most striking in the “Portraits of Power” exhibit, both for its size and for the variety of expressions that emanate from the 69 distinct portraits.

“In making the images of power, [Avedon] always wanted to move beyond the face to find the person,” Roth said.

For the Washington set fascinated by people, power and politics, the Avedon exhibit offers a lengthy gaze that will last longer than election season.