The group that gathered in the board room of the Cumberland Chamber of Commerce Monday afternoon was William Donald Schaefer's kind of crowd: a dozen pillars of this Western Maryland city's business community, all eager to listen to the Baltimore miracle worker and expected candidate for governor.

"It's a pleasure to welcome the next governor," began Jerry Womack, the chairman of the chamber's board of directors and an executive of First National Bank.

"Those are sweet words," replied the Baltimore mayor, deftly acknowledging his all-but-certain Democratic candidacy without confirming it.

For 15 minutes, Schaefer treated the executives to a discourse on his favorite subject and strong suit as a candidate -- economic development. In a sometimes rambling presentation, he talked of the interrelated needs of all areas of the state and the importance of Maryland having a forceful leader who will actively court jobs and industry.

But when the talk turned to the flagging fortunes of Cumberland's downtown mall, Schaefer suddenly grew impatient.

"Your mall is attractive, but something is missing," he said, launching into a table-pounding lecture on the need for Cumberland's business community to be "upbeat" and avoid "gloom."

"Business climate is partly attitude," insisted Schaefer as he abruptly put on his coat and headed for the door, summarily declaring by his imminent exit that the meeting was over.

It may not have been what the board of directors of the Cumberland Chamber of Commerce had expected, but it was vintage Schaefer: seductive and scolding, almost within the same breath. "Government by intimidation," is how one veteran Baltimore politician describes it.

With a commanding early lead over his Democratic opponent, Attorney General Stephen H. Sachs, Schaefer has the freedom to be as nice or as testy as he wants. With $1 million in his war chest already and a 2 1/2-to-1 lead in the polls, Schaefer is the 500-pound gorilla of Maryland politics.

Schaefer's appeal to voters, as evidenced by a day of thinly disguised campaigning in Cumberland, has little to do with his skills as a public campaigner, which are ragged at best. Speaking to several dozen community leaders at Del. Casper Taylor's (D-Washington) downtown restaurant, Schaefer wanders from subject to subject, like a drunken sailor ricocheting off lamposts.

He speaks in snippets of thoughts rather than sentences. He can't decide whether to call Del. Tim Finan (D-Allegany) "Tom" or "Tim," so he finally settles on "Del. Finan." He mistakenly refers to one of Cumberland's largest industries as "Springfield-Kelly" rather than Kelly-Springfield, but with his charm turns the gaffe into an asset.

Neither does it have much to do with issues. The mayor's spiel depends heavily on one subject, economic development, but even that is a collection of generalities. When he touches on another issue, education, he uses a shorthand that appears to leave his audience a bit baffled.

But for all that, the frumpy figure with the elastic mug is a triumph wherever he goes. The public looks at Schaefer, and in a kind of political Rorschach test, sees Harborplace, one of his urban renewal triumphs. Baltimore is to some a code word for urban resurrection, and Baltimore is Schaefer.

Schaefer is seen by some as the stern but lovable father figure, who one moment can snuggle up to the Cumberland business people, and in the next reproach them for not trying hard enough to do their homework before turning to him for help.

The mayor is perceived as an impatient and driven man who gets things done and who demands the best from his underlings. In that, Schaefer is benefiting from the style set during the seven years of Harry Hughes' governorship, a laissez-faire tenure that surveys show has left the public yearning for a more hands-on governor.

The mayor understands that in his gut. Although his public criticisms of Hughes are mild compared with his private feelings about the governor, the subliminal message is that Schaefer would have a much firmer hand on the throttle of government.

The irony is that Sachs, who also hails from the activist school of governing, has not appeared to benefit as much from the perceived lethargy of the Hughes years.

A further irony is that 1986, coming as it does after a year in which the state has been rocked by financial scandal, ought to be ripe for the reformist zeal of a Sachs rather than the insider politics of a Schaefer. The mayor has made almost a religion out of his close ties to the business community, yet seems totally undamaged by the savings and loan scandal, the central lesson of which is that government cannot have an incestuous relationship with industry.

Most insiders expect the Schaefer-Sachs contest to narrow once the mayor declares his candidacy, an announcement not expected until the spring. That will give Sachs only four or five months to reduce the mayor to human proportions.