Quoting Scripture and invoking her Catholic faith, U.S. Sen. Mary Landrieu said farewell to her colleagues in a speech on the Senate floor Thursday.

“All I can feel is, actually, joy,” Landrieu said near the beginning of her 30-minute speech. She said a sense of “extraordinary peace” came over her a few days before Saturday’s Senate runoff in Louisiana, which she lost to Republican U.S. Rep. Bill Cassidy, of Baton Rouge.

Landrieu, 59, has served three six-year terms in the Senate, and her 2008 campaign marks the last time a Democrat won a statewide election in Louisiana. Her defeat Saturday pushed the net gain for Republicans in this year’s Senate elections to nine, and they will hold a 54-46 majority in the Congress taking office in January.

Landrieu cited several senators and other public officials as her mentors, including the late Lindy Boggs, a Democratic congresswoman from New Orleans, and former Louisiana Democratic U.S. Sens. J. Bennett Johnston and John Breaux. She also credited her Republican seatmate, David Vitter, for helping pass key legislation, and praised former Republican U.S. Reps. Jim McCrery, from northwest Louisiana, and Richard Baker, of Baton Rouge, as well as current House members Cedric Richmond, a New Orleans Democrat, and Charles Boustany, a Lafayette Republican.

“If you want to accomplish really big things here, really great things, really generational things, you certainly cannot do that alone,” she said.

Landrieu thanked the labor movement for supporting her first run for public office when she was 22 and for working with her ever since. She singled out the black caucus in Congress for special mention, thanking it “for being a such a great partner with me and helping me understand about compassion, forgiveness and faithfulness.”

She thanked her parents first, saying, “Our family is truly blessed by their sacrificial leadership.”

Landrieu is the oldest of nine children of former New Orleans Mayor Moon Landrieu and his wife, Verna. Her father served as mayor for eight years while she was in high school in New Orleans and in college at LSU. In 1979, two years after her graduation, she was elected to the state House of Representatives from New Orleans, and eight years later, she was elected state treasurer.

In 1995, she ran for governor but lost; the next year, she was elected to the U.S. Senate, defeating her Republican opponent by fewer than 6,000 votes. She was re-elected in 2002 and 2008 before losing her bid for a fourth term this year.

Speaking in a relaxed tone and gesturing with a pair of eyeglasses in her hand, Landrieu spent much of her time on the floor discussing the issues she held out as the most important in her career: coastal protection and restoration, national energy independence, education, adoption and foster parenting, and disaster recovery.

In remarks after the speech, she cited as her No. 1 accomplishment the passage in 2006 of the Gulf of Mexico Energy Security Act, which dedicates a substantial share of the revenue the federal government collects from offshore oil and gas drilling in the Gulf to the Gulf states for coastal restoration, wetlands protection and flood control.

“It’s just been a joy,” she said on the floor, “but I know that God is calling me to a different place. I’m not the least bit sad, and I’m not the least bit afraid.

“It’s just been a remarkable opportunity to serve with all of you.”

Landrieu was followed on the floor by Vitter and several other senators, Democratic and Republican, who spoke in tribute to her.

After her speech, Landrieu said she will continue to work on the issues important to her, but as a “private citizen.” She and her husband own a home on Capitol Hill in Washington; eventually, she said, they plan to retire to Louisiana.

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