In the months leading up to Tuesday’s election, two candidates for district attorney in the 22nd Judicial District never broke character: Brian Trainor, chief deputy for the St. Tammany Parish Sheriff’s Office, was Mr. Law Enforcement, and Covington attorney Warren Montgomery was the crusading reformer.

After eliminating Alan Black and Roy Burns in the primary, the two now go head-to-head in a Dec. 6 runoff to succeed Walter Reed. His decision not to seek a sixth term in office amid a federal grand jury probe opened the door to the first new district attorney for St. Tammany and Washington parishes in 30 years.

The first- and second-place finishers are unlikely to deviate from their carefully scripted formulas as they approach the runoff.

On election night, Trainor further polished his law enforcement badge with an endorsement from Washington Parish Sheriff Randy Seal. Trainor’s boss, St. Tammany Parish Sheriff Jack Strain, has been a vocal backer of his second-in-command.

The day after the primary, Montgomery called a news conference outside the courthouse to announce he had the support of Burns, who also had positioned himself as a reform-minded political outsider.

Part two of the electoral contest promises to be rough-and-tumble. Candidates already had begun taking off the gloves in the run-up to Tuesday’s voting, although most of the sniping was directed at front-runner Trainor, who captured 38 percent of the vote to Montgomery’s 25 percent.

Montgomery went strongly on the offensive, issuing a flier that painted Trainor as the consummate political insider and stressed his ties to the embattled Reed and Strain. A cartoon video on YouTube was even more unsparing, casting Montgomery as a sword-wielding knight fighting corruption, including the Sheriff of Rottingham and his minion, the so-called Dark Knight.

Trainor took some shots of his own, characterizing his opponents as criminal defense lawyers who have spent their careers trying to keep criminals out of jail, while he, as an assistant district attorney and then as chief deputy for the St. Tammany Sheriff’s Office, has spent his career locking up bad guys.

When Burns endorsed Montgomery on Wednesday, Trainor fired off a scathing response. “It doesn’t surprise me to see that these two criminal defense lawyers are sticking together,” he said via email. “Evidently they want a district attorney who will be weaker on crime and better for their criminal clients. Together these two have represented some of the most heinous criminals the north shore has ever seen.”

Both candidates say they are trying to play down the negative tone, even as they continue to assail each other.

Montgomery called his flier simply a comparison piece. “Everything in it was accurate. … The only one who said it was an attack piece was Brian Trainor,’’ he said.

Trainor said he was “not taking a shot at any of these men’s characters’’ but was merely contrasting their records with his own experience as a prosecutor, which is what a district attorney is.

Ready responses

The two candidates enter the final month of the campaign with a good idea of their rival’s game plan and have ready responses to the anticipated criticisms.

Trainor said that while opponents have tried to paint his law enforcement experience as a negative, he sees it as a positive, and he said that’s how it resonates with voters he talks to on the campaign trail who want someone with a proven record of fighting crime.

While his job as chief deputy — from which he is on leave for the campaign — is administrative, Trainor said he has ridden along on patrols and has made arrests, slapped on handcuffs and testified in court.

Montgomery bristles at Trainor’s claim that he’s made a living keeping criminals out of jail. “All my felony trials were pro bono, each and every one. I was appointed by a judge to represent poor persons who needed a lawyer,’’ he said, accusing Trainor of failing to fully understand the criminal justice system.

Neutral observers suggest that both candidates have exaggerated their prosecutorial résumés. Trainor was the chief of the misdemeanor section under Reed; Montgomery’s work as a federal prosecutor was of short duration — and decades ago.

The candidates have taken similar shots at each other. Trainor said Montgomery hasn’t tried a case in 30 years, while the YouTube video from the Montgomery camp called Trainor the prosecutor of “carriage violations.’’

Montgomery counters that he conducted about 20 felony jury trials, handling the opening and closing arguments and cross-examinations. He said they involved complicated factual and legal issues, going after drug cartels and organized drug crime. As a defense attorney, he said, he’s also handled complicated issues. “Trainor has only tried misdemeanor cases and traffic tickets,’’ he said.

Trainor, who worked in the District Attorney’s Office for eight years, said he did the job he was assigned to do, but he called it the busiest section of the office — and the one that involved the most interaction with the public.

But in weeks when misdemeanor court was not in session, Trainor said, he would voluntarily assist on other trials. He didn’t quantify the number of felony trials he was involved with, saying it was a handful.

Campaign math

With the field of candidates cut in half, the two camps are doing the math.

Trainor said he didn’t anticipate a primary win and that the 38 percent of the vote he received was in line with his campaign’s expectations. He ran in second place in Washington Parish, with 30 percent of the votes cast there.

Montgomery is looking not so much at his 25 percent but at the votes Trainor didn’t get. “The other three candidates were in opposition,” he said, “so that 62 percent of the vote — they did not want the machine, the status quo, the good ol’ boy network. I am their natural candidate because I have the best qualifications and the least connections, in comparison to Mr. Trainor.’’

That leaves a big question: Who — if anyone — will Black support in the runoff?

Both candidates have spoken to the third-place finisher, who is a native of Bogalusa and has had a law practice for many years in Slidell, areas where he showed strength. Trainor said his understanding was that Black wanted the weekend to consider what to do. Montgomery said he didn’t know what Black plans.

“Mr. Black is going to do what he’s going to do. … Obviously, I would like his endorsement. I would like his voters to support me,’’ Montgomery said.

Trainor said he has already gotten encouraging words from some of Black’s supporters, who told him while he was out campaigning that they would have voted for him if Black had not been in the race.

Black did not return a call for comment about his plans.

The other parish

While both candidates are from St. Tammany Parish, they are not ignoring the other, less populous part of the 22nd Judicial District.

Montgomery was in Washington Parish on Friday morning meeting with lawyers and police officers, he said. Trainor was headed to a high school football game in Franklinton.

For Montgomery, who jumped into the race late, the challenge is name recognition. While observers say he surged in the last days of the primary, the candidate said he didn’t have the money to do a poll. An initial one in September showed that voters were concerned about political corruption and crime.

Montgomery said he thought he fit the profile of what voters were looking for but that they had to get to know him. He lacks the big political endorsements of his rival. He also said he will have to make serious fundraising efforts after a primary campaign that was largely self-funded.

Trainor, who raised by far the most money and also spent the most in the primary, said it’s expensive to get the word out to voters. He said he is reaching out to his base again, reconnecting with his supporters and reminding them that the election isn’t over yet. “We’re going to keep hitting the streets with our message,’’ he said.

Follow Sara Pagones on Twitter, @spagonesadvocat.