"While Congressman Boustany is honored to have been encouraged to run for the U.S. Senate in 2014, he remains dedicated to the 3rd Congressional District of South Louisiana. He was humbled to receive so much support from across the state," Boustany's spokesman, Neal Patel, said in an email to The Hill.

Patel noted that Boustany's position on the Ways and Means Committee — where he holds the chairmanship of the Oversight Subcommittee — allows him "to focus on issues important to Louisiana ranging from trade, to comprehensive tax reform, to health care."

Boustany's decision not to run still leaves a deep bench of potential contenders for the race, which Republicans consider a pickup opportunity in 2014. Louisiana's increasingly red tint will make Landrieu's reelection campaign a difficult one.

GOP Reps. 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 and Bill Cassidy, as well as former Rep. Jeff Landry, are all still considering challenging her, and Lt. Gov. Jay Dardenne may also launch a bid.