It's been 40 years since the Rev. Andrew Gunn knocked on doors to speak against gambling in Maryland, and he's noticing how things have changed.

Some for the better: The essay about the evils of slots that he handed out to lawmakers in Annapolis last week took only minutes to duplicate, a great relief from the days when making copies on the mimeograph machine in his church basement drove him crazy.

Some for the worse: To call on politicians in both the Senate and House buildings, he had to spend a big chunk of his day waiting to pass through security.

You can't win. And that is also the sum of the argument he's making as he knocks on the doors of state delegates and senators to discuss his opposition to slot machines.

Andrew Gunn knows all about them. As a young Methodist minister in Charles County in 1958, he watched a woman pass by the one-armed bandits in the food store and return some cans of food to the shelves so she could drop a few more quarters into the machines. He wanted to weep.

He counseled families affected by divorce, alcoholism, drugs and the brothels on U.S. 301 and complained loudly about it to local officials until one evening, when he stopped by High's as usual to pick up milk -- his five children were young then -- a man pulled up behind him and stuck something in his ribs and warned him to leave Charles County.

Back then, he says, he had the advantage of being young and stupid. After he realized that local lawmakers and sheriffs depended for their salaries on the slots industry, the first telephone call he made to try to close down the industry was to the governor.

Ultimately Gunn and his supporters were successful in getting rid of slots from Charles and three other Maryland counties.

Now 72 and living in Germantown, he has pledged to wage a similarly tenacious battle. Legalized theft, he calls slots, explaining that the machines are fixed to give owners 70 to 90 percent of the take.

His is also the moral argument, the one to add to practical issues like whether slots can or should solve a budget deficit and whether they have a social or economic cost.

"For a lot of these politicians," he says, "it's just a game. But it's going to hurt an awful lot of human beings."

So far he has spent five full days calling on lawmakers. He started with his own district, Montgomery County, whose delegates are largely opposed to slots.

Isn't this a little like preaching to the choir?

Not exactly, he says.

The fact is, some people in his district are on the fence. He is on the way right now to see some.

Dressed in a cozy wool sweater and sport coat, with his gray hair, silver glasses, khaki raincoat over one arm, navy briefcase in the hand, and enough papers with names and numbers in his pocket to confuse him, Gunn doesn't appear to be anyone who would cause trouble, except perhaps in the pulpit.

But at a strategy meeting of like-minded people earlier in the day, he gave this piece of advice: Don't act like a gentleman.

"Sweet and nice is fine," he says. "But when I start speaking to someone earnestly, they listen to me."

He has heard that Sen. Patrick J. Hogan, a Democrat, may be taking a position in favor of slots, and he heads to the senator's office to convince him it would be the wrong thing to do.