Nazi leader Frank Collin, represented by a Jewish lawyer and appearing before a black judge, won a legal battle yesterday that he said makes it likely he will call off a Nazi march set for Sunday in the heavily Jewish Chicago suburb of Skokie.

"If the ruling is as it appears, the Skokie march is off," Collin told reporters after U.S. District Court Judge George N. Leighton ruled that the Nazis have a constitutional right to hold a rally in Marquette Park on the blue-collar South Side of Chicago without posting an insurance bond.

"My overall goal always was Marquette Park - speaking to my own white people rather than a mob of howling creatures in the streets of Skokie," Collin said.

Judge Leighton announced in court that he will be attending a judicial conference out of town today, but that when he returns tomorrow he will sign an order instructing the Chicago Park District to issue a permit for the Nazis to demonstrate on July 9 in Marquette Park.

Collin said he will review the final order with his lawyer, David Goldberger of the American Civil Liberties Union, and hold a press conference tomorrow to announce his final decision about the Skokie march. "I am pleased with what Judge Leighton has said," Collin added, "but if there is any ambiguity (in the order), we will go to Skokie Sunday."

Chicago Jewish leaders said the cancellation of the Skokie march wouldn't alter their plans to hold a massive counter demonstration Sunday at a stadium five blocks from the planned Nazi march site. But they said that if the Nazis did not demonstrated, the attendance probably would be less than the 50,000 they have predicted.

In the face of threats of violence by the militant Jewsih Defense League, Gov. James R. Thompson has put the Illinois National Guard on alert to go to Skokie Sunday if the Nazis go ahead with the march.

Bonnie Pechter, national director of the league, said her group still plans to confront the Nazis "with violence" at a demonstration Saturday afternoon in front of the Kluczynski Federal Building in downtown Chicago. Collin announced this week that the downtown demonstration would be held as a "warmup" for the Skokie march.

Leighton's action yesterday came on an ACLU petition to modify an injunction he issued nearly a year ago preventing the Chicago Park District from requiring the Nazis to post a $350,000 insurance bond before holding a rally in Marquette Park.

The park district responded to the initial injunction by lowering the insurance requirement to $60,000. Goldberger then petitioned Leighton to hold park officials in contempt of court, contending that they knew the Nazis were unable to obtain insurance in any amount.

Leighton ruled yesterday morning that Goldberger's motion was improper, but gave him permission to file instead a petition to modify the injunction so that it would preclude the use of any insurance requirement to block the rally.

Goldberger filed the new motion yesterday afternoon, and despite objections from Chicago Park District attorney Richard Troy, Leighton said he would grant it because First Amendment principles are involved.

The judge left confusion in the minds of lawyers on both sides, however, when he added that "details of the modification [of the injunction] will have to await a hearing." He would not elaborate on what he meant, and no hearing was scheduled.

"Is this preliminary relief" Troy asked him.

"I don't want to categorize it as preliminary," Leighton replied.

Pechter of the JDL said, "What this does is give Collin a way to save face and cancel the Skokie march. We know he is afraid to go to Skokie, and wants to get out of it any way he can."

"I'm perfectly willing to go to Skokie - and I will go if this ruling is not satisfactory," Collin said. "I will have a definite announcement about it Thursday."