MAXIE, LA., JUNE 30 -- On Friday night in Cajun country, David Duke was the only show in town. Old cars and pickups lined Route 13 for a half-mile in both directions outside the B&M Gas Station and Restaurant. A Budweiser truck was parked in the gravel lot between the store and the gas pumps, and the brew flowed free and easy as farmers, oil field workers, fishermen, retired deputy sheriffs and office workers waited for their man Duke, the 39-year-old former Ku Klux Klansman now running for the U.S. Senate in Louisiana.

What he really liked about Duke, said rice farmer Jimbo Hundley, wearing a blue and white Duke T-shirt and a Duke baseball cap, was simply this: "He says in public what we all talk about in private."

"Ever see anyone who could get this many people to a little dump like this?" marveled J.C. Henderson, an 85-year-old retired sheriff, as he gazed at a crowd of about 400. "Huey Long couldn't draw a crowd like this here!"

Mark Faul, the 23-year-old owner of the Egan Food Store, was telling the latest joke about David Duke to four of his friends. Every sentence in the joke had a slur in it. The racist fable was illustrative of the mentality of the younger crowd at B&M's on this Friday night.

It went like this: Duke runs out of gas driving down Interstate 10. He gets out of his car and walks, head down, along the side of the roadway, until he kicks a lamp. Out jumps a black genie. When he finds out that he has to grant three wishes to none other than David Duke, the black genie decides that for every wish he grants Duke, blacks will get the same -- only twice as much. Duke asks for five gallons of gasoline. Every black person in America gets 10 gallons. Duke asks for $2 million. Every black gets $4 million. Duke figures it out. For his third wish he says he'd like to be half-dead.

Faul and his buddies, between gulps of beer, laughed and slurred their way through the story. Two young women in the crowd laughed along but appeared anxious whenever Faul used the standard racist slur when talking about blacks. "Oh Mark," they said. "Don't. Please. It's ugly." When it was over, the women talked about how they liked Duke because he was going to put welfare mothers to work.

Wendell Martin, a 49-year-old oil field salesman, was eager to hear Duke. He had had his fill of the incumbent senator, Democrat J. Bennett Johnston, Martin said. "We want somebody to represent us, not {Sen. Edward M.} Ted Kennedy {D-Mass.} and the rest of them communists." Johnston lost Martin's vote when he turned against Robert H. Bork for the Supreme Court. That showed Johnston had played too much tennis with Kennedy, Martin said, and forgotten about the people back home.

Duke arrived at the gathering protected by a cordon of deputy sheriffs. Fresh from a day on the job as a freshman Republican in the Louisiana House, the president of the anti-black National Association for the Advancement of White People appeared better dressed than his supporters: a pressed white shirt, finely knitted pants, a blue tie. His face was red and ruddy, his hair stylishly trimmed. And he was ready to say publicly what the crowd was talking about privately.

First he went after what he called "the massive rising welfare class." He never used racial slurs. He rarely even used the word black. He has mastered other methods, other codes. One day, Duke told the Maxie crowd, a doctor from northern Louisiana called him on the House floor to tell him that a welfare mother was in his office who had three illegitimate daughters, each of whom had three illegitimate children -- all fathered by the same man.

Oaths of disapproval moved through the throng. Duke then slipped into his version of black slang as he mimicked the black patient explaining the situation to the doctor: "Well, doctor, we gets a bigger welfare check, and Johnny, he gets more money for his card game."

Duke's lecture continued: Get drugs out of the welfare system. Stop paying welfare mothers who just have babies. There are whole sections of the Southwest "where they don't even speak English. Spanish is the language." America is losing its morals more each day. No more affirmative action. An end to minority set-asides. "True equal rights for everyone."

As for his critics, the media elites, the black caucus in the legislature, the national political parties, Duke said they were all trying to smear him. They call him a racist. "Racist," he said. "They say the word and it's like a stink bomb to anyone it's said about. I'm called a racist every day. But I will not be silenced by an epithet."

No one knows how far David Duke can carry his race-based campaign. The political experts in New Orleans did not think he could win a seat in the state legislature, but he did in a special election in early 1989. Now they say he cannot win the Senate race in which Duke is one of three major candidates, the other two being incumbent Johnston and state Sen. Ben Bagert of New Orleans, who has the backing of the state GOP. In Louisiana, candidates run in a single open primary election regardless of party. Polls show Johnston in the lead with support from slightly more than 40 percent of the voters; Duke is backed by 20 to 25 percent, while Bagert's support is in single digits. If Johnston gets less than 50 percent in the Oct. 6 primary, there will be a runoff between him and the man in second place.

Like all ambitious politicians, Duke is discovering that while true believers abound on the edges of the political spectrum, most voters reside in the middle. He is now in the difficult position of trying to attract votes on a broad scale while still building a racial movement based on white power and resentment. As a result, he usually tries to tone down his speeches and interviews, but not too much. Whenever he slips across the line, or whenever his incantations push his supporters across the line, Duke is quick to issue a disclaimer.

At a rally in Shreveport, Duke went after one of his favorite targets, the New Orleans newspaper. "You know the New Orleans Times-Picayune is down on me," Duke told supporters. "But you know who owns the Times-Picayune, don't you?"

From the front row came the reply: "Jews. Jews. Jews."

When asked about the incident later, Duke said he did not endorse that kind of reaction. His public position now is that he has nothing against blacks or Jews; he is just speaking out for the rights of working-class white Christians. He tries to dismiss his days in the Knights of the Ku Klux Klan by saying, as he did in Maxie Friday night: "When I was a young kid, I was a rascal, I'll admit it. But I've grown up." The statement strikes a chord with supporters, who respond with wild cheers.

"He's purged most of his language of the neo-fascist right," said Lance Hill, director of the Louisiana Coalition Against Racism and Nazism. "He used to talk about the founding white majority, which was a code word for supremacy. He would talk more openly about the Zionist-controlled press. Now his standard speech is a kind of soft racist populism with an appeal that is to both class and race. He inveighs against elites who manipulate the lives of working people, and at the same time targets blacks and minorities who he believes or suggests are leeching from society."

Last year, Duke was not always so cautious. As late as June 1989, Duke was selling neo-Nazi materials in his Metairie district legislative office, including "Imperium," which is dedicated to Adolf Hitler and calls Jews "distorters of culture"; "Did Six Million Really Die? The Truth at Last," which says the Holocaust was a hoax; and videotapes of American Nazi Party founder George Lincoln Rockwell. Soon thereafter Duke said he stopped ordering "books of a controversial nature."

Later that year, on Nov. 29, Duke gave an interview to Tulane University student Abby Kaplan. During the course of the tape-recorded interview, Duke said he thought it was a mistake for the United States to have entered World War II. Hitler, he said, was right about some of his racial theories. He said there are genetic differences between the races and "blacks generally . . . have more of a tendency to act in antisocial ways."

Since he entered the Louisiana House last year as the representative from the 81st District in the New Orleans suburb of Metairie, Duke has tried to mold his racial philosophies into a legislative agenda. All of his bills have targeted blacks except one requiring drug tests for teenagers seeking driver's licenses. The others are aimed at welfare mothers, drug dealers in housing projects and affirmative action and minority set-aside programs.

On most of his programs, Duke could count on about 20 supporters in the House. "Those guys have voting records compatible with his views and have for years," said civil liberties lobbyist Russell Henderson. "They just leave their sheets in the closet." But timing and politics allowed Duke to expand his base for one bill calling for elimination of minority set-aside programs in the state. It came up just when legislators from Acadiana -- Cajun country -- were upset with several black representatives for not voting in favor of a lottery. They pushed Duke's bill through in a fit of anger.

"Duke caused a divisiveness that was not here before he came," said state Rep. Odon Bacque (I-Lafayette). "He brings the black-white issue very much to the forefront." The 13 black members of the Louisiana House will not talk to Duke. They turn their backs whenever he rises to speak. "We have nothing to talk to him about," said Rep. Diana Bajoie (D-New Orleans). "His whole agenda is anti-black."

The light was fading in Maxie, but the crowd was turned on. Duke was on a roll, talking about the American flag and Robert Bork and how if Bennett Johnston had not led the fight against Bork, the Supreme Court never would have allowed people to burn the flag.

"The far left ran the same smear campaign against Robert Bork that they're running against me," he said. "But all the attacks, all the smears and all the lies they tell about me in this campaign will only make this electoral victory bigger! It will give it more impact! I can promise you when David Duke speaks when he's a U.S. senator, people will listen."

Duke stood on the flatbed truck under overhead lights. When he stopped saying in public what most of his listeners say to each other in private, they started to chant -- first one, then a handful, then the whole crowd: "Duke! Duke! Duke! Duke!"

"This is no longer a Senate election," said Hill of the Louisiana Coalition Against Racism and Nazism, which has been tracking Duke's rise. "It has nothing to do with the Senate. Nothing to do with Bennett Johnston. It is a referendum on the future, a referendum on hate."