The election of a Republican president last month didn't bode well for Kenneth Polite Jr., the top federal prosecutor in New Orleans who took office in 2013 with the support of then-Democratic Sen. Mary Landrieu and President Barack Obama.

U.S. attorneys serve at the pleasure of the president, and they typically offer their resignations upon a changing of the guard in the White House. 

Several names have surfaced as potential replacements for Polite, including Wendy Vitter, a former local prosecutor who is the wife of outgoing Republican U.S. Sen. David Vitter, and Eric Skrmetta, a member of the state Public Service Commission who served as co-chairman of President-elect Donald Trump's Louisiana campaign.

But in an unexpected twist, Polite has won the backing of the state's two highest-ranking Republican officeholders, an endorsement that could complicate Trump's decision as to who should serve as the top federal prosecutor in a city long notorious for corruption and civil-rights abuses.

State Attorney General Jeff Landry sent letters Friday to Trump, U.S. Sen. Bill Cassidy and U.S. Rep. Steve Scalise urging them to retain Polite as U.S. attorney for the Eastern District of Louisiana and describing his three-year tenure as "without controversy and extremely effective."

"He is actively involved in the prosecution of human trafficking crimes and has successfully prosecuted violent gang leaders such as Telly Hankton," Landry wrote, calling Polite and his wife "pillars of the community."

"As a registered independent, Mr. Polite is not a political partisan or influenced by party politics," he added. "I believe that his record warrants serious consideration, and I strongly recommend him for retention in his position."

Landry registered his support two weeks after Lt. Gov. Billy Nungesser, also a Republican, sent a similar letter to Vice President-elect Mike Pence, calling Polite's resumé "unsurpassed."

A product of the Lower 9th Ward and the former Calliope public housing complex, Polite was the valedictorian of De La Salle High School before graduating from Harvard University and the Georgetown University Law Center. He worked as a federal prosecutor in New York before returning to New Orleans.

"He is in a prime position to serve the public at large and to find solutions to our crime issues, not just prosecute them," Nungesser wrote. "He serves as a role model to our youth and has established a rapport with them that is difficult for a law enforcement officer to achieve, much less the U.S. attorney."

The son of a New Orleans police officer, Polite has earned the respect of the Louisiana law enforcement community, said Col. Mike Edmonson, the State Police superintendent. "I think he's done a phenomenal job," Edmonson said. "He's always been available, like all three of the U.S. attorneys in the state, and I think that speaks volumes."  

Polite on Saturday described the Landry and Nungesser letters as "a testament to the outstanding work" of his entire office. "I am humbled by the bipartisan support for my service as U.S. attorney," he added. 

While U.S. attorneys generally are replaced with the changing of administrations, there have been prominent exceptions. Trump already has agreed to retain Preet Bharara, an aggressive U.S. attorney in Manhattan nominated by Obama who has developed a national reputation for taking on public and financial-industry corruption. 

Former New Orleans U.S. Attorney Jim Letten, a career prosecutor, was appointed by President George W. Bush, a Republican, but remained in office in the Eastern District of Louisiana after Obama was elected in 2008. Letten, a registered Republican, was the longest-serving U.S. attorney in the country by the time he stepped down in 2012 amid an online commenting scandal involving two of his top lieutenants. 

"It's not unprecedented that an incumbent, even from a different political party, would remain in that position despite a change of political parties in control of the White House," said Harry Rosenberg, a former U.S. attorney in New Orleans who, along with dozens of his counterparts, was swept out of office when President Bill Clinton took office. "But I think the odds are typically in favor of a replacement."

Senators from an incoming president's party typically play a big part in selecting U.S. attorneys. But Polite's popularity could place Cassidy, a Republican, in a tricky spot, given the outsized role David Vitter played in Cassidy's 2014 victory over Mary Landrieu, said Joshua Stockley, a political scientist at the University of Louisiana at Monroe. 

"For these individuals to indicate their support for a Democratic appointment is unusual," Stockley said of the Landry and Nungesser letters. "Polite has either turned out to be far more conservative, perhaps, than presumed, or he's proved to be far more competent. These are Republicans saying he may have been appointed by a Democrat, but he does a very good job, so let's not make him an automatic casualty of political war." 

Landry said he spoke at length with Cassidy on Saturday and found the senator to be "very receptive" to the prospect of retaining Polite as U.S. attorney. Wendy Vitter is "certainly qualified" for the position, Landry said, but no one contacted him about her being interested the post.

"With everything going on right now in New Orleans, I think we need the steady hand of someone who knows the city, and that's Kenneth," Landry said in a telephone interview.

He added that he and Polite have worked to thaw a longstanding "chill" that existed between the state and federal prosecutors. "I can't say enough about how easy he's been to work with," Landry said. 

Follow Jim Mustian on Twitter, @JimMustian.