Baltimore mayor and all-but-certain Democratic gubernatorial candidate William Donald Schaefer said last night he supports the limited return of slot machine gambling on Maryland's Eastern Shore as long as it is strictly controlled and the revenues are used for charitable purposes.

"I'm not interested in Maryland becoming a gambling state like it once was, but I've seen the good slot machines do on the Eastern Shore," Schaefer said in an interview after an appearance at a "Marylanders for Schaefer" reception in north Bethesda.

Schaefer indicated that if he were governor he would not veto slot machine legislation approved by the General Assembly in the legislative session that concluded Monday. That position puts him at odds with both Gov. Harry Hughes, who has promised to veto it, and Attorney General Stephen H. Sachs, against whom Schaefer would run in the Democratic primary.

Sachs, reached by telephone last night, said he is unalterably opposed to the reintroduction of slot machines.

"Slots are a symbol of a corrupt and sad chapter in Maryland's history," he said. "It took us years to close that chapter. I'm very sensitive to that; the mayor apparently is not."

The disagreement on the emotionally charged issue of slot machines served to highlight the fundamental choice likely awaiting Maryland Democrats in the gubernatorial primary Sept. 9 and offered a preview of the campaign expected to begin soon in earnest.

Schaefer's comments on slot machines came on a night when his all-but-declared candidacy came further out in the open as the mayor attended several of the hundreds of "Marylanders for Schaefer" receptions being held across the state as a means of urging him to run for the State House.

He said that he views slot machine revenues as an acceptable means of finding a "continual source" of funds for charitable and fraternal organizations, which he said are finding it increasingly difficult to raise money.

Schaefer said that as long as there was "strict accountability to see where the money goes," he would not oppose the return of slot machines, but that he did not favor the introduction of other forms of gambling such as dog racing.