It was the first night session of the Maryland General Assembly, traditionally a time for after-hours play, when a familier figure walked through the doors of a favorite drinking spot here.

There was Marvin Mandel, slowly working his way through a crowd of friendly legislators, shaking hands and exchanging warms greetings. Once seated, he and his wife and old friends spendt the night swapping stories.

Forced from office Oct. 7 after his sentencing on political corruption charges, Mandel is definitely not taking the Richard Nixon route of retreat and isolation. He still calls state bureaucrats and engages them in long discussions about policies.he still attends political fund raising events where he is quickly joined by loyal admirers.

Some of his friends say he is just seeking relief from the tedium of unemployment, that he is "restless and bored and a little nostalgic for the old days," as one put it Others like State Treasurer William S. James put it differently. "He lived and died for this (politics) for so long its hard to break old habits."

State Personnel Secretary Henry Bosz said his former boss has callecd him several times in recent months, inquiring about labor relations among state employees and proposed pay raises for state workers.

"We talk just as if the calendar had been rolled back two or three years," said Bosz. "As I handicap this guy, he's not going to sit back in a rocking chair and vegetate."

Budget Secretary Thomas W. Schmidt said he also has been called by Mandel, who asked about state rev- enues, the fiscal outlook and the budget proposal under preparation. "Gov. Mandel lived with the budget. It's awfully hard after all those years to divorce yourself from it."

According to friends of the suspended governor, Man del is trying to maintain a high visibility as a matter of pride. Becoming a recluse would indicate he is ashamed of himself, friends say.

One longtime associate said Mandel decided to grant an interview on Baltimore television in November "to show people he would face them. He wanted them to see he wasn't going into hiding" after 25 years in government.

Mandel derives great satisfaction, friends, say, from the recognition and admiring reponse he receives from people and political allies he occasionally sees in public places.

"That's all he's got left," according to one of Mandel's government associates. "He lost his office. He lost his staff. He lost his home. All he's got left is his friends."

When he left for his Florida vacation last month Mandel told a television reporter that he would begin work as soon as he returned in the New Year. But, friends say, Mandel is still without work.

It remains unclear how Mandel can pay for his $675-a-month estate in Severna Park (as he says he does), private schools for his second wife's children and expensive clothes. During his trial he said he was financially insolvent.

When he walked into the Anapolis night spot this week, Mandel was tanned from his vacation in Florida and looked much heavier than during his days as governor. He told friends he is his most relaxed in years.

When he arrives at Annapolis restaurants and bars, Mandel is welcomed almost like a visiting foreign dignitary. Friendly legislators and lobbyists pass by his table and pay him tribute.

Old friends tell him he looks well and he responds that the feels well and asks them personal questions about thmselves. He offers chilly responses to inquiring reporters.

"I think Mandel misses it like any ex-delegate," said Del. Daniel Minnick (D-Baltimore County), who has seen Mandel at nightspots recently. "It's so much a part of him. It gets in the blood."

It is not known how Mandel spends his days aside from lengthy telephone calls to friends and onetime political allies. In recent weeks, he has been involved in a dispute with his first wife, Barbara, ove alimony payments.

Last fall, Mandel called Ocean City Mayor Harry Kelly, and, according to Kelly's Original recollection, offered state aid to help clean up the damage from heavy flooding in Ocean CIty. Since then, Kelly has backed off his original recollection, offered state aid to help clean up the damage from heavy flooding inOcean City. Since then, Kelly has backed off his originial recollection of the conversation, while insisting that Mandel did call him.