Most of the big questions on the District's long-debated entry into legalized gambling have already been answered, or at least seem well on the way to resolution. It's the little questions that are keeping Brant Coopersmith awake nights.

The biggest question of all-- whether D.C. residents wanted to have legal lotteries and bingo games--was answered last November. After rejecting a proposal that would have authorized dog tracks and jai alai frontons, District residents voted overwhelmingly in favor of legalized "numbers," lotteries and bingo games.

The next major question--whether Congress will provide the money to implement the voter initiative--is still up in the air. Just before the August break, a key House subcommittee knocked out the money the city had requested to run the lottery. The betting, however, is that the Senate, and then the full Congress, will restore that money.

Coopersmith, who is chairman of the Lottery and Charitable Games Control Board set up to administer the voter-authorized games, frets about the effort by some members of Congress to overrule the wishes of the local residents.

But it's the little stuff that is on his mind.

"Everybody's been focusing on the lottery part of the legislation, and it's true that is the major element of the law," he said the other day. "But for us on the board, the bingo and raffle regulations are the hardest part.

"We don't want people to make a living out of bingo. What we would like to see--what we think the voters had in mind--are the charitable fund-raising bingo games of the sort the Catholic churches and others have been holding, with members of the sponsoring groups running the games. We don't like the idea of professional bingo operators."

On the other hand, he said, the board would not like to freeze out those groups that want to run legitimate fund-raisers but might not be able to run the games themselves. "I'm thinking of groups whose members are blind or old or otherwise handicapped, for instance, or, say, mental health groups, who need their volunteers on the telephones rather than running bingo games. Is it fair to tell them they they can't hire a management company to run their games?

"And if the charity doesn't have a place to hold the game, shouldn't the management company be able to supply the hall? But once you do that, you've got professional game operators. Is that something we should discourage, or is it something we should encourage as a new business opportunity? Should there be a limit on the number of hours a day, or days a week, a bingo game can operate?"

Coopersmith said he and his fellow board members are also fretting over rules for running lotteries. The small lotteries--the PTA raffling off a Thanksgiving turkey or a TV set--are no problem. What concerns the board are the big lotteries like the recent one in Northern Virginia in which the prize was a $115,000 house.

Should the charity running the lottery have full possession of the prize before the tickets are sold? (In the Northern Virginia case, the owner allowed a boys' club to sell 2,000 chances at $100 each, with the first $113,000 going to the owner.)

What, if anything, should the board do to keep lotteries from becoming just a clever way of selling real estate? What limits, if any, should it set on the amount of profit going to the original owner before the sponsoring charity gets its cut? Should the cost of the tickets be tax-deductible as a charitable contribution? Should there be dollar or percentage limits on the amount of lottery earnings a charity can take for overhead? On the amount of the handle to be paid out in prizes?

Or should the board simply require full disclosure of the number of lottery tickets to be sold, the approximate odds of winning and the amount of money actually used for charitable purposes?

Should the board make rules that would prevent the establishment of lottery entrepreneurs? ("Let us run a lottery in the name of your charity; we'll do all the work, collect our fee out of the proceeds and turn the profits over to you, and it won't cost you a dime or a lick of work.")

The questions are tough, but the city is lucky to have on the initial control board people who are willing to tackle them now. The rules they work out will go a long way toward determining whether the games remain "clean."