"I'm not going to run for the U.S. Senate," he told LaPolitics Weekly.

"This fell in my lap. I didn't go out looking for it. So I'm not going to prolong the question any longer. I love what I'm doing and I will continue to do that for the balance of my term."

Dardenne had previously indicated he was considering a run for Landrieu's seat. She is considered by Republicans one of the most vulnerable Democrats in the nation, running in a red state President Obama lost by double digits in 2012, and a handful of Republicans have expressed their interest in the seat.

But despite Louisiana's Republican tilt, Landrieu has increased her margin of victory in each subsequent U.S. Senate election she has competed in. In 2008, she defeated state treasurer John Neely Kennedy 52-46 percent. Her bid next year will likely be aided by her brother, Mitch Landrieu, who became mayor of New Orleans in 2010.

Just last week, another contender — Rep. Charles BoustanyCharles William BoustanyLobbying world Dems face hard choice for State of the Union response Americans worried about retirement should look to employee ownership MORE (R-La.) — said he would not seek the Republican nomination. Rep. Bill Cassidy is likely to jump in, but he has not yet made his bid official. Rep. John FlemingJohn Calvin FlemingCoast Guard suspends search for missing Ohio plane Freedom Caucus member to bring up bill on impeaching IRS chief GOP seeks to make it 52 MORE, former Rep. Jeff Landry and former Gov. Buddy Roemer's son, Chas, is considering it as well.

This post has been updated from its previous version.