Former U.S. Sen. Mary Landrieu, D-La., has signed on as a consultant with a D.C. law and lobbying firm, the firm announced Tuesday.

Landrieu lost her bid for a fourth term in the Senate last fall to Republican Bill Cassidy. She has owned a home for many years in Washington, where her husband is a real-estate agent.

The lobbying firm, Van Ness Feldman, represents numerous clients in the energy industry and is recognized for its expertise in energy matters. Landrieu is a longtime champion of the industry who served as chairwoman of the Senate Energy & Natural Resources Committee for most of 2014.

“I am proud to join Van Ness Feldman,” Landrieu said in a statement on the firm’s website. “I have always respected the firm and worked closely with them during my 18 years in the Senate. Their substantive and sophisticated approach to important public policy issues in the areas of energy, the environment and natural resources was a major factor in my decision-making process.”

Richard Agnew, chairman of Van Ness Feldman, said on the site, “Mary is known as being one of the most effective, passionate and bipartisan members of the Senate. Her knowledge, experience and leadership skills will be a tremendous asset to our clients. Her collaborative style, tenacity and focus on results will advance our firm’s core practice areas.”

The firm’s clients include TransCanada, the company seeking federal approval to complete the long-stalled Keystone XL pipeline from the oil-producing tar sands of Canada to refineries on the Texas Gulf Coast.

Landrieu pushed strongly for a bill to require the White House to issue the necessary permits for the pipeline but failed to win over enough of her fellow Senate Democrats to gain approval of the legislation, which was opposed by environmental groups. Her failure was used against her in the Senate campaign by Cassidy, who also supports the pipeline.

The 2015-16 Congress, with a new Republican majority in the Senate, sent a Keystone-approval bill to Democratic President Barack Obama, but he killed it with a veto. Obama has said he wants to wait for completion of an administration review of the project before deciding on it.

The firm also counts clients in the liquefied natural gas sector and successfully lobbied for federal approval last year of another pet Landrieu project: the Cameron Sempra LNG export terminal in Hackberry. The company broke ground on the terminal in October.

Landrieu will join a long-serving former Democratic congressman, Norm Dicks, of Washington state, in heading up Van Ness Feldman’s public policy operation.

Landrieu, who cannot work as an actual lobbyist until January 2017 under federal rules for outgoing members of Congress, joins several other former members of the Louisiana congressional delegation in the ranks of Washington’s professional persuaders, including John Breaux, another Democratic ex-senator, and Bob Livingston and Billy Tauzin, both former Republican congressmen.

Landrieu earlier this spring also accepted a position as a consultant to the Walton Family Foundation, a charitable organization of the family that made its fortune on Wal-Mart stores.

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