Making a rare move Tuesday, the Louisiana Republican Party backed a GOP challenger over a Republican incumbent.

Jeff Landry, a former congressman from New Iberia, was backed by the state party in his bid to oust a fellow Republican, incumbent Louisiana Attorney General Buddy Caldwell .

The last time the Republican Party endorsed a challenger over an incumbent statewide official was in 1991, when it shunned Gov. Buddy Roemer in favor of challenger former U.S. Rep. Clyde Holloway, R-Forest Hill, who is now on the Louisiana Public Service Commission. Roemer had switched from Democrat to Republican several months before he launched a re-election bid.

Roger Villere, chairman of the state GOP, said Tuesday the announcement was not a slap at Caldwell, who is seeking a third term. Landry is just the better-qualified candidate and is the most conservative, he said.

“It’s time for an honest, ethical and hardworking attorney general,” Villere said, adding that Landry is a “lifelong Republican.”

Caldwell switched from Democrat to Republican in early 2011 prior to seeking a second term, which he won without opposition. He has fought the Obama administration on key issues, joining lawsuits contesting such things as the federal health care revamp.

However, Caldwell has been unable to shed the RINO label (Republican in name only), at least among some of the GOPers. An email circulated by a Republican committee member Christian Gil, of St. Mary, underscored that sentiment: “Lifelong Democrat Buddy Caldwell only switched to save his public taxpayer-funded job.”

Late Tuesday, Caldwell issued a statement through his campaign: “The endorsement of Jeff Landry doesn’t change anything from our perspective. We would have welcomed the endorsement, but we weren’t counting on it. The state party has never endorsed me before, so it might have been bad luck to get it this time.”

But it was clear that Caldwell thought the party made a mistake. “It’s unnerving to me that the statewide Republican Party would even think about endorsing someone who has never tried a civil or criminal case in court. I’m not sure, really, what his qualifications are,” Caldwell said.

A majority of the Republican Party’s ruling committee petitioned for an executive committee endorsement of Landry, a former congressman from New Iberia.

The seven-member executive committee unanimously gave Landry the nod.

Landry, who is running a well-funded campaign, previously received endorsements from high-profile Republicans including U.S. House Majority Whip Steve Scalise, of Jefferson, and GOP presidential candidate Rick Santorum, a former U.S. senator from Pennsylvania, as well as the Family Research Council leader Tony Perkins, a former state representative from Pride.

Landry reported $1.35 million in cash on hand three months prior to the Oct. 24 primary election — slightly more than the $1.05 million in Caldwell’s account. A third Republican — attorney Marty Maley has just under $10,000 on hand. Landry and Caldwell have both bolstered their accounts with personal loans.

Landry recently injected $350,000. “It’s important that the person on the ballot put some skin in the game,” Landry said.

Landry welcomed the support at a news conference and talked about his credentials, including work in law enforcement, as an attorney and in Congress, where he opposed President Barack Obama’s federal health care revamp as well as his order shutting down drilling off the Gulf Coast after the BP disaster.

Landry said he also opposed “wasteful spending” and cut his congressional office expenses. He criticized the $60 million Caldwell spends annually for office operations. (The Attorney General’s Office budget appropriation is $66 million for the current fiscal year.)

“We need to do a better job returning some of that money back to the taxpayer,” he said.

Landry said he would get more specific on other problems with Caldwell’s tenure in the coming days.

“I will apply the law fairly and without malice,” Landry said.

Follow Marsha Shuler on Twitter, @MarshaShulerCNB. For more coverage of the State Capitol, follow Louisiana Politics at http://blogs.the advocate.com/politicsblog/.