CHICAGO, DEC. 2 -- In a scene so bizarre and raw that four television stations carried it to its near-dawn conclusion, the City Council today elected Democrat Eugene Sawyer to succeed the late Mayor Harold Washington.

The pandemonium ended at 4 a.m., 10 1/2 hours after the special meeting to elect an acting mayor was scheduled to begin.

One alderman wore a bulletproof vest; another, shouting, climbed on his desk in the council chambers as thousands of demonstrators chanted in the street outside.

Some council members were called "thieves" and "vultures"; others were accused of "inciting mob rule" during four stormy hours of debate that did not begin until after midnight.

When it was over, Sawyer, a longtime South Side ward boss, became the acting mayor until April 1989, when a special general election will be held.

Sawyer is a reluctant chief executive.

A veteran alderman, Sawyer wasn't so much elected as he was pushed into office by white aldermen after some of Sawyer's black allies on the City Council had announced they wanted to postpone balloting until Friday because Sawyer did not have enough support among black citizens to govern.

Sawyer defeated Alderman Timothy C. Evans, Mayor Washington's council floor leader and chief political spokesman, with the votes of 23 white aldermen, many of them longtime archrivals of Washington, and six blacks. Evans got 19 votes. There were two abstentions on the 50-member council.

Evans supporters, lacking a majority vote on the council, tried to put public pressure on the city's 18 black aldermen with a massive protest. Democratic presidential candidate Jesse L. Jackson was one of the architects of this strategy.

It almost worked. About 4,000 demonstrators jammed the lobby of City Hall and spilled out over half a block of LaSalle Street outside. The crowd waved signs and chanted "Uncle Tom, Uncle Tom Sawyer" and "No Deals, No Deals."

Sawyer, the council's president pro tempore, clearly had enough votes to win. But he apparently was so unnerved by the demonstrators that he repeatedly delayed proceedings as he pondered whether to continue his candidacy.

The council meeting was scheduled to begin at 5:30 p.m. Tuesday. But Sawyer didn't make his first appearence in the chamber until about 9:20 p.m., and he stayed only moments.

Sawyer's knees buckled as he spotted Mary Ella Smith, the late mayor's fiancee, and he appeared faint. A bodyguard helped him from the crowded room.

He did not return until after midnight. "I think Gene lost his nerve," said state Rep. Al Ronan who had been lining up votes for Sawyer.

The other 47 aldermen waited, and the spectators in the chamber grew unruly. At one point, scores of spectators waved dollar bills in the air and shouted, "No deals, no deals."

Rivals Sawyer and Evans held several conferences throughout the evening. Groups of their supporters also caucused.

Alderman Richard Mell, who represents a white ethnic ward, burst out of one meeting shouting, "We've got a new mayor. We've got a new mayor. Gene Sawyer."

Forty-five minutes later, Sawyer's top black lieutenants told reporters that their candidate had decided to throw in the towel for the evening. They said he wanted to postpone voting until Friday because, as one put it, "he does not have the support of the black community."

"Gene Sawyer can't be elected totally by white aldermen," said Alderman William Beavers. "He has to have the support of the black community."

Eventually, Sawyer returned for a vote, but that took place after nearly four hours of delaying tactics by Evans forces.

Jesse Jackson and other allies of Mayor Washington had been trying to build public support for Evans since last Friday in a series of rallies and at memorial services for Washington, who died last week. The effort peaked at a city-sponsored memorial service Monday attended by about 11,000 people. Jackson and others urged that Washington supporters protest at Tuesday's council meeting.

Beavers conceded that Evans, who, by virtue of his position as Washington's floor leader, was better known than Sawyer, had far more popular support among black voters than his candidate. But Sawyer had the votes on the City Council.

However, his black council support began to erode after Monday's memorial service. Black aldermen reported that their offices were flooded with telephone calls from Evans supporters. At least five Sawyer supporters reported receiving death threats, and others expressed uneasiness about the crowd at City Hall.

"The public will simply not tolerate a pretender to the throne," Evans told reporters. "There's no mob activity here. People are simply asking, entreating that aldermen listen to them."

White aldermen supporting Sawyer became incredulous that their candidate appeared unwilling to go ahead with a vote. They feared that Sawyer would lose if voting was postponed.

"We have the votes. Gene Sawyer can walk in here and be mayor of Chicago in five minutes," said Alderman Roman Pucinski, who complained that the demonstrations had done "irreparable harm" to the city's image and made it look like "a banana republic."

A stream of supporters visited Sawyer, trying to prop him up and persuade him to continue. Sawyer also called in ministers to pray with him.

Visitors left Sawyer, uncertain whether he was in or out of the race. "He has had a number of threats and he is concerned about his family," Pucinski said at one point. Edward A. Burke, another white alderman supporting Sawyer, said the candidate felt tired and ill.

At 12:10 a.m., when Sawyer reappeared in public for the first time in almost three hours, he looked like a boxer who had been revived with smelling salts.

He moved slowly into the chamber without exchanging a word with lieutenants. He looked detached and disinterested. Three bodyguards stationed themselves behind his chair. The name-calling and shouting now broke out in earnest. It continued for four hours. Evans supporters accused Sawyer of forming an unholy alliance with white leaders who had opposed Mayor Washington at almost every step during his five years in office.

They called Sawyer supporters "obstructionists," "thieves" and "vultures" and claimed Evans was the logical heir of the "Harold Washington legacy."

Alderman Dorothy Tillman, an Evans supporter, turned to Sawyer to plead, "Don't you understand what you're doing today? Don't get caught on the wrong side of history. Don't be used. Don't be used by them."

Alderman Jesus Garcia called Sawyer "a fine gentleman," but added, "The problem is he has changed his mind 10 times. He doesn't know if he wants to be mayor or not."

Sawyer supporters accused Evans forces of trying to win with "threats," "intimidation" and "mob rule." They described Sawyer, whose ward regularly delivers the largest Democratic majorities in the city, as much an ally of Washington as Evans was.

They repeatedly noted that Sawyer was the first alderman to endorse Washington's candidacy in 1983, when he won his first term, and had been a loyalist ever since.

Sawyer backers bristled at the attacks from Evans forces. "The man I support is no thief. I don't believe he has cut any deals," said Alderman Ernest Jones. "I believe he's faithful to his wife. I believe he is good to his children."

Alderman William Henry, one of Sawyer's top strategists, defended deal-making as part of politics.

Sawyer regained strength as the debate continued. After his predawn election, he said: "The reform movement initiated by Mayor Washington will remain intact and go forward. It will continued untainted by special interests for the rich and powerful . . . . Harold, my buddy, I will never, never, never let you down."

Special correspondent Janice Kramer contributed to this report.