The 2015 Louisiana gubernatorial campaign has been tame so far, at least publicly: The four major candidates have focused on meat-and-potatoes issues, such as state budget problems, traffic congestion and the Common Core education standards.

But in the shadows, a parallel, and much less polite, campaign has been unfolding, this one having to do with lingering questions about presumptive front-runner U.S. Sen. David Vitter’s history with prostitutes.

There, a small army of journalists, bloggers, private eyes and opposition research specialists has been chasing rumors and tales about the senator’s murky actions. Of course, Vitter’s major opponents — Lt. Gov. Jay Dardenne, Public Service Commissioner Scott Angelle and state Rep. John Bel Edwards — have more than a passing interest in the subject.

“It’s been hanging around this campaign since the day he announced,” said Bernie Pinsonat, a Baton Rouge-based pollster and political consultant.

This week, with a month and a half to go before the Oct. 24 primary, two developments dragged the topic out of the margins and back into the public arena.

First, Baton Rouge television reporter Derek Myers was fired Tuesday after he confronted Vitter with questions about the issue. Myers claimed he lost his job because the Vitter campaign threatened to pull its ads from the station. Although the station’s general manager denied the claim, the story spread like wildfire on websites and social media.

Next, a political action committee launched an anti-Vitter ad on television. Exactly who is behind the group and how much money its donors are putting behind the ad is not yet clear, but it was airing statewide as of Friday.

The anti-Vitter faction — including an entity called Gumbo PAC — is trying to dredge up and disseminate enough information to keep voters from sending Vitter into the Governor’s Mansion in January. With Vitter holding a huge lead in fundraising and enjoying a large statewide profile, some think a new and sordid disclosure — or a cleverly packaged attack using existing information — may be the only thing that will derail him.

“Any new revelations could hurt him deeply with women voters, if not all voters,” said Pearson Cross, a political science professor at the University of Louisiana at Lafayette. “The stakes are high.”

But no new information has emerged yet. In fact, no major new facts have emerged since 2007, when Vitter vaguely admitted to a “very serious sin” and refused to go into further details. In 2010, he easily weathered a Senate re-election campaign, in which his opponent was unable to dig up any fresh scandal.

That has not deterred Gumbo PAC — whose director, Trey Ourso, formerly headed the state Democratic Party — and bloggers, such as Lamar White Jr., from taking up the hunt about prostitutes and other stories about women involving Vitter.

The senator contends that he is being targeted by the left. But the primary beneficiaries of a Vitter scandal would probably be his GOP opponents, Dardenne and Angelle.

And White, an unabashed liberal who last year wrote stories questioning timesheets filed by then-U.S. Rep. Bill Cassidy in connection with a job at LSU, said that “the majority of people who have approached me with information are Republican conservatives.”

Jason Brad Berry, a New Orleans blogger who runs the American Zombie website and worked with White on the Cassidy stories, agrees, saying the information about Vitter “is coming from many different sides.”

The problem is, most of it appears suspect. Berry, who has been looking into Vitter since 2010, when he won re-election, has published only one post culled from his research, and that was an audio interview with a woman who denied rumors that she had serviced Vitter as a call girl.

“I haven’t been able to directly source anything else up until now,” he said. “Vitter has made a lot of enemies.” Berry added that he’s pursuing a lead he believes is promising.

Vitter was first publicly linked to prostitutes in 2002, when Vincent Bruno, a Republican activist in Jefferson Parish, told a radio audience that Vitter had consorted in New Orleans with a call girl named Wendy Cortez.

The New Orleans-based Louisiana Weekly reported Bruno’s claim. Vitter was then a congressman whose district mostly included Jefferson and St. Tammany parishes.

A month later, Vitter appeared on a New Orleans radio show hosted by Jeff Crouere, who is known for his conservative views. Caller David Bellinger, who styles himself “the Flaming Liberal,” asked Vitter about Cortez. Vitter said he was the victim of “vicious rumors” that he dismissed as “lies.”

A second caller asking him about Cortez led Vitter to label Bruno “a thug and a liar.”

In a recent interview, Bruno said he immediately pledged to sue Vitter, but that Vitter sent him a letter of apology.

In the interview, Bruno said Cortez had first told her story to him in 1999, when he was working for the congressional campaign of former Gov. David Treen, who narrowly lost the special election to Vitter. Bruno said he believed Cortez’s account, but Treen did not want to publicize it.

“My concern is that he violated the law,” said Bruno, a former New Orleans policeman who has been engaged in various controversies over the years.

In 2002, Vitter announced he was dropping plans to run for governor the following year, after marriage counseling sessions with his wife, Wendy.

The sessions were prompted not by “any dramatic issue or event,” Vitter said in a prepared statement, according to The Advocate, but by “cumulative stress” related to his job, rearing four young children, running a congressional re-election race from his home and traveling the state to gauge his chances in the governor’s race.

“Our counseling sessions have been so effective that they’ve led us to the rather obvious conclusion that it’s not time to run for governor,” Vitter said.

In July 2007, three years after he won election to the Senate, Hustler magazine confronted Vitter with a phone log showing he had received calls from the so-called “D.C. Madam,” who was accused of running a high-end prostitution ring in Washington. It would be revealed several days later that Vitter had taken several of the madam’s calls during roll call votes in the House.

Vitter released a statement admitting to a “very serious sin” but didn’t provide specifics.

A day later, the so-called “Canal Street Madam,” Jeanette Maier — who had been at the center of a prostitution scandal that exploded in New Orleans in 2002 — told WDSU-TV that Vitter had been one of her clients, paying $300 per hour for sex, at her Mid-City brothel and in hotel rooms.

“He seems to be one of the nicest men and most honorable men I’ve ever met,” Maier said.

Her attorney, Vinny Mosca, said, however, that he had “absolutely no recollection of David Vitter’s name ever appearing on any document, book or list, or having any association” with Maier.

A day after Maier went public, so did Cortez, telling The Times-Picayune that she had regularly serviced the congressman at a French Quarter apartment at the corner of Dumaine and Dauphine streets. She later provided graphic details of their encounters in a video interview with Hustler to promote a photo spread of her in the magazine.

Vitter didn’t respond to either woman’s claims. By then, he had gone into seclusion. He didn’t resurface until a week later, when he appeared for five minutes before the press at the Sheraton Hotel in Metairie.

There, he apologized and said he had sought forgiveness from God and his wife, but did not admit to consorting with the D.C. Madam, nor with any other prostitute. Wendy Vitter, who had been standing next to her husband, told the media that he indeed had her steadfast support.

They left without taking questions.

Critics pounced because Vitter has always cast himself as a man of honor, upholding family values, morality and ethics in a political milieu that he often portrays as corrupt.

In 2008, Vitter’s attorney said he would invoke the 5th Amendment — the right against self-incrimination — if called to testify in the prosecution of the D.C. Madam, Deborah Jeane Palfrey.

In the end, he did not have to testify. Palfrey was convicted of prostitution, and two weeks later, she hung herself. Dan Moldea, the investigative reporter who uncovered Vitter’s connection with Palfrey in 2007, said in a recent interview that the madam, a repeat offender, had told him she could not bear another prison term.

Questions about Vitter’s dealings with prostitutes resurfaced in 2010 when he had to face the voters for the first time since the scandal broke. His challenger, then-U.S. Rep. Charlie Melancon, hired an opposition research firm that compiled a dossier on Vitter, and Melancon produced an ad highlighting Vitter’s links to prostitutes.

But the fullest airing of the issue occurred during nearly four minutes of a statewide televised debate between the candidates, and there, Vitter showed off the stubborn, disciplined unwillingness to address the topic that he has demonstrated ever since he spoke to the press at the Sheraton.

WAFB-TV reporter Greg Meriwether asked Vitter to identify the “serious sin” he had confessed to three years earlier. But Vitter would not do so. Instead, he repeated his 2007 comments that he had received forgiveness from his wife and God and said he had received an outpouring of prayers and support from constituents afterward.

“It was truly humbling,” Vitter said of the reaction.

WWL-TV anchor Dennis Woltering jumped in to ask Vitter whether he had violated the law in committing the unspecified sin.

Vitter said he had spoken directly on the issue to voters in 2007. He added: “Now I’m looking forward. I’m not looking back.”

Meriwether tried again, asking Vitter to give a yes or no answer on whether he had violated the law.

“You can stay fixated on that,” Vitter said, repeating that he wanted to look forward.

Woltering interjected that Vitter still hadn’t answered the questions.

“I think the people of Louisiana have understood exactly what I said to them,” Vitter replied. “I think they want me to focus on the key challenges we face as a state and as a country. That’s what they tell me directly. It may not be what the media badgers me with.”

Vitter ultimately trounced Melancon in the election.

The Advocate requested an interview with Vitter for this article, but campaign spokesman Luke Bolar said Vitter had completely addressed questions about the issue in 2010.

The 30-second anti-Vitter ad that began airing throughout Louisiana on Wednesday shows news articles about the D.C. Madam and about Cortez’s allegation, along with a brief video clip of Cortez discussing her relationship with Vitter. The Vitter campaign succeeded in getting television stations to pull the ad Thursday because it contained a misstatement about a former staffer to Vitter who had been arrested. The ad’s sponsors tweaked it and it was back on the air Friday.

Vitter’s three gubernatorial opponents have mostly opted not to bring up the prostitution issue directly in the campaign.

“I have not frequented prostitution and certainly have not done that sitting on the floor of the United States Congress,” Dardenne said at a campaign forum in late August when asked how he differed from Vitter. (It was only one of the differences he cited.) Dardenne didn’t respond to a request from The Advocate for an interview on the subject.

Edwards, in an interview, was asked the relevance of the prostitution issue.

“At the very least,” he replied, “the people want to elect someone they feel proud of and can look up to and someone they can tell their children to be proud of.” He declined to be more specific.

Angelle didn’t agree to an interview, instead sending an email questioning its relevancy to the campaign. He said it is “up to the people of Louisiana to decide, but I don’t think this race is about David Vitter’s past … it’s about Louisiana’s future.”