A legion of admirers packed the Polish Falcon Hall here Tuesday night, spilling out onto the street and chanting for an appearance by their political leader.

They roared approval when the small figure, his boyish face aged by time and hard times, fought through the crowd to acknowledge the election victory that allowed him to reclaim his seat on the City Council, where he began his political career nearly 14 years ago.

Former mayor Dennis J. Kucinich--"Dennis the Menace" as he was known to some--is back.

The 36-year-old Democrat, whose tenure as mayor from 1977 to 1979 was one of the most turbulent periods in Cleveland's history, ended a political exile Tuesday by winning a runoff election for the council seat made vacant by Councilman Joseph Kowalski's death. Kucinich won the seat in a blue-collar ward with 4,120 votes, or 56 percent, in the eight-candidate field, followed by Edward W. Rybka, a lawyer, who got 3,210 votes.

Kucinich served on the council from 1969 to 1975.

As mayor, he waged relentless battles with the banks, the business community and the City Council, and presided over the fiscal downfall of the first major American city since the Depression to go into default. A self-described champion of the "little people," he survived an unprecedented recall election by just 236 votes.

Kucinich achieved a measure of national fame, but local voters tired of the confrontations. In 1979 they replaced him with a low-key, businesslike Republican, George V. Voinovich. Under Voinovich, Cleveland's financial status has improved, and Cleveland calls itself "the comeback city."

Kucinich insists that he has altered his combative style and is prepared to cooperate.

"I suppose you could say I don't live and breathe politics anymore, that my family is the most important thing in my life now," he said. "I've learned a lot of lessons in the last few years. I've learned there are ways to bring about political solutions other than to attack."

He also learned that the job market can be brutal for controversial former mayors. After his defeat, he contracted with Random House to publish his autobiography, but indications are that Random House has dropped plans for publication.

Aside from an occasional college lecture, Kucinich was unemployed. He applied unsuccessfully for several jobs on the West Coast, and last year lost a bid for the Democratic nomination for Ohio secretary of state. His 1982 federal income tax return listed total earnings of $38.

In the council race, Kucinich's many political opponents did not roll out the red carpet in welcome. In their lust to defeat him, they inadvertently helped him.

His first break came when a beat-Kucinich strategy of the Greater Cleveland Growth Association, the city's chamber of commerce, was made public. This group, which is about as popular in Kucinich's 12th Ward as the soot from the nearby steel mills, gave him an opportunity to score at the expense of those he calls "the fat cats."

Next, the city's most powerful black leader and longtime Kucinich foe, Council President George L. Forbes, made a televised speech saying, "Dennis Kucinich screwed a whole lot of people in this town, and a lot of people are waiting to screw him when he comes back. Including me."

As Rybka said, Forbes' statement proved "lethal" in a ward where he is not held in high esteem.

Voinovich, who makes no secret of his intense dislike for Kucinich's politics, mailed two letters to ward voters warning that Kucinich's enemies in the council would deprive the ward of badly needed improvements.

But the warnings went unheeded, and Kucinich assumed the $21,780 a year post today.