The 27th Ward, a desolate patchwork of vacant lots, dilapidated houses, dingy storefronts and high-rise housing projects, is the epitome of the Chicago Democratic organization's "plantation politics" on the city's West Side.

Ninety-four percent of its residents are black, 99 percent of its votes are Democratic. Yet for the past 20 years, the ward boss has been a white man, sewer commissioner Edward A. (Big Ed) Quigley, and like most black wards here, it has been shortchanged in city services despite its party loyalty.

These days, Quigley's once all-powerful blessing is becoming a kiss of political death. His candidate for mayor, incumbent Jane M. Byrne, received only 22 percent of the vote in the Feb. 22 Democratic primary, and his handpicked choice as alderman--sewer department employe Mattie Coleman, his secretary--was forced into a runoff on Tuesday, the first in ward history.

Quigley blames the political stumblings on complacent precinct workers. He blames criticism of his effectiveness as ward boss on "slobs," "punks" and black bigots on the make.

"This is all racial and nothing else," Quigley said. "It's just because I'm white and it's a popular thing to say, 'He's white and he's not doing nothing.' Anyone who's . . . been around, they can speak for me . . . I'm not ashamed of what the hell I've done or tried to do."

What is really dragging Quigley down is a fervent political crusade among Chicago's 1.2 million blacks, who have belatedly been mobilized by the spirit of the civil rights movement and galvanized by years of what they perceive as political insults from the party they have served so loyally.

Now not only are they rebelling against Quigley and other political overseers, black and white, but they also are extraordinarily unified behind Rep. Harold Washington's (D-Ill.) bid in Tuesday's election to become the city's first black mayor.

For many, a Washington victory has become an all-or-nothing proposition.

He has served in public office for nearly two decades, they say. He is a lawyer. He is a native son. Perhaps most important, he is the undisputed winner of the Democratic primary.

The party, which dominates city politics, has delivered victory to every nominee over the past 50 years, including some, blacks say, with lesser qualifications than Washington's. And through the years, they say, blacks have dutifully supported party nominees, including some they disliked.

Now it is Washington's and their turn to capture the grand prize of city politics, they say, and no ifs, ands or buts about it.

"Why in the world wouldn't a Democrat win? " asked schoolteacher Beth Jones, shopping for groceries at a Jewel Super Market on the South Side. "He's got all the qualifications. If he were white, there'd be no question."

At the same store, housewife Fannie Mason, a born-again Christian wearing a rainbow button that read, "Christians Aren't Perfect. Just Forgiven," said Washington as mayor would be a an example of what blacks can achieve.

"They think we're all ignorant," she said.

Would she hold up this man with numerous past tax problems and unpaid bills as a role model for her four daughters, she was asked.

"If you look at all the candidates' pasts--those running for mayor, governor, alderman, any position," she responded, "everybody's got a skeleton in the closet. Why bring up the past? "

A few blocks away, baker Jim Matthews sipped a drink at The Swingers, a middle-class bar.

"They've been saying, 'Go back to school. Pull yourself up by your bootstraps," he said. "We followed the system. We went out there and voted. We did what they told us to do.

"If Washington loses, it would boost the hostility in this city. We'd have to do it their way--just go out and take what you need. Forget the rules."

Printer Edward Roberts was on a stool nearby.

"If he doesn't win, he just doesn't win," Roberts said. "He fought for it, he tried it and he lost. I don't look for blacks to riot or cause any reaction. I look for whites to do that . I don't carry any animosity."

Nathaniel Clay, an activist jour- nalist who headed the community coalition that registered an estimated 200,000 black voters before the primary, was less optimistic, contending that blacks have turned to politics out of desperation.

"It would be a great, great tragedy . . . if Harold does not win," he said. "It will cause so much disappointment in the community that most black people will be reluctant to ever listen to those of us who have told them to try the electoral process."

The prospect of Washington's losing has put some Chicago blacks on a political war footing. One is Cook County Commissioner John H. Stroger Jr., the Democratic boss of the 8th Ward on the South Side.

Last week, Stroger and his aides gathered nearly 200 precinct captains and election workers in his storefront ward headquarters on Cottage Grove Avenue, packed them shoulder-to-shoulder between the walls where signs proclaimed, "A Voteless People Is a Hopeless People."

The ward workers were reminded that many blacks like them would never have been hired on city jobs were it not for ward organizations like Stroger's.

Then they were exhorted to turn out no less than 85 percent of the ward's voters to help stop the white Democratic steamroller for Republican Bernard E. Epton, Washington's opponent.

"I think there's a conspiracy to steal this election from us," Stroger said, and many in the audience nodded their heads in agreement. "They're out to get you. What are you going to do about it?"

"On election day, I want you out there walking and talking," he said, "and I don't care if you have to cry and beg. I want you to get 'em out. This should be a crusade in our community, because they have made it a crusade in their community to keep you out."

Chicago's black political uprising is the latest chapter in a long and colorful past, dating at least back to the 1920s when the black South Side boss, Big Ed Wright, hobnobbed with the white bosses at the Appomattox Club, dutifully delivered black votes to the Republican machine and used his city hall connections to prevent interference in the flourishing illegal numbers games.

At that time, the South Side was the center of most of Chicago's black community, made up of many educated but underemployed blacks whose families had left the South in search of better opportunities, just like their white ethnic counterparts.

When Edward J. Kelly and the Irish took over the political machine in 1933, Chicago politics turned Democratic. Blacks followed Wright's successor (and one of Washington's mentors), William L. Dawson, into the Democratic ranks.

In 1955, black voters, their ranks swelled by an influx of less-educated southerners lured by well-paid though unskilled jobs during World War II, helped Richard J. Daley win the mayor's office.

Yet for the ensuing two decades, blacks garnered only limited political power. There were five black alderman from the South Side and one from the West Side.

Now there are 16 black aldermen on the 50-member City Council, the largest single ethnic block, and nine black ward committeemen, the nominal ward bosses.

Blacks recognized that they had been controlled because whites were registered to vote and they were not. Last year, they launched a massive voter registration campaign financed largely by 8th Ward businessman Edward G. Gardner, chairman of the Soft Sheen hair products company, who spent $125,000 to $150,000 to market voter registration and participation in the same way businessmen market products.

"Once they got registered and found out what power they had, blacks really began to flex their muscles," Gardner said. "Now we know our strength, we know our power. It's just a new day in the black community here in Chicago."

And it is a new day in Big Ed Quigley's 27th Ward on the West Side, where Richard Barnett, an independent political activist, is lining up his ducks.

If Wallace Davis Jr. defeats Mat- tie Coleman, Quigley no longer will have a voice on the City Council. If Harold Washington defeats Bernard Epton, Barnett expects Quigley to be fired as head of the sewer department with its 1,235 patronage jobs, in time for next year's elections for ward committeeman, Quigley's job.