Voters in Michigan's 16th Congressional District go to the polls Tuesday to pick from a crowded field a successor to former congressman Charles Diggs Jr., who resigned this summer to begin serving a three-year federal prison sentence for receiving payroll kickbacks from his staff.

Diggs, who had been the nation's senior black congressman and who, with his father, had controlled politics on Detroit's tough east side for more than four decades, left a political vacuum in his district. That vacuum has drawn 13 candidates into an intense, confusing Democratic primary.

The winner of the Democratic nomination is virtually certain to win the general election in the 13th District, one of the most heavily Democratic in the nation.

The man to beat in the Democratic race is 70-year-old retired Judge George Crockett Jr., who has the backing of Detroit Mayor Coleman Young, the United Auto Workers Union and Diggs himself.

Crockett has been a prominent, often controversial, member of Detroit's legal community for 40 years. In the 1950s he was Coleman Young's attorney when the youthful labor organizer was called before the House Committee on Un-American Activities. Crockett spent four months in a federal prison in 1952, after being cited for contempt of court while defending a client who had been accused of being a communist.

In 1969 Crockett attained hero status among Detroit's blacks. Following the shooting of a white policeman, Detroit police has surrounded and arrested 147 black men, women and children who were in the New Bethel church, charging they were conspirators to the killing. Crockett, then a Recorders (criminal) Court judge, went to a police station at 5:30 the following morning, set up a makeshift court and began releasing the prisoners. Crockett was vilified for weeks in the press and by local politicians, and both houses of the state legislature called for his impeachment. But his actions subsequently were upheld by higher courts.

Despite his stature and establishment backing, Crockett has had no free ride. An early strategy urging blacks to unite behind him to avoid dividing their vote fell apart when the lone white candidate the Rev. David Eberhard, was ruled off the ballot on a technicality.

Crockett's opponents accuse him of being too old and aloof, and there is a lingering suspicion that he intends to serve merely as a caretaker until Diggs is free to run again.

"Judge Crockett has an almost legendary record of service, but I ask people, 'Do you want to vote for a legend or what is best for Detroit?'" says the Rev. Nicholas Hood III, 28, a soft-spoken, issue-oriented contender in the race. Hood has the backing of former U.N. ambassador Andrew Young.

Two other leading candidates in the field are 65-year-old state Sen. David Holmes Jr., a 20-year state legislator who outfoxed Crockett's backers to win the Democratic party endorsement, and Detroit City Councilman Clyde Cleveland, 45, a street-wise politician.

"The campaign has not been nearly as much concerned with issues as with personalities," says Crockett. "I'm sure you wouldn't find much difference in any of the candidates. All of us come from the same background -- the ghetto, the urban center. The 13th District is 75 percent black.

"We are all hurting and want to do something about it."