Montgomery County's close battle between incumbent executive Sidney Kramer and challenger Neal Potter turned hostile yesterday: Kramer accused Potter of "dishonest" and "dirty" politics in response to an attack on Kramer's real estate holdings and campaign contributions from developers.

Kramer, reacting to a pro-Potter brochure that a Kramer campaign official called "the sleaziest piece of literature" ever seen in Montgomery politics, said that instead of debating the issues, Potter has chosen to "get a shovel and muck around in the slime."

The pamphlet, handed out by Potter yesterday as he campaigned at a Metro station, contains a message in which Montgomery County State's Attorney Andrew L. Sonner says, "Kramer has placed the interests of his family-owned real estate business and his rich developer friends ahead of our citizens' interests."

Kramer's denunciation of the literature, later echoed by his wife, Betty Mae, in an emotional defense of her husband, seemed to startle several hundred supporters who had gathered at a Silver Spring hotel for a reception at which Gov. William Donald Schaefer endorsed Kramer in Tuesday's Democratic primary.

"No one on earth knows Sid Kramer the way I do," said Betty Mae Kramer, accusing Sonner of using his office to try to come up with some dirt on Kramer and, failing that, resorting to "innuendo" and "suggestion."

Potter said of the brochure, printed under the authority of Citizens for Sonner: "I didn't write it. I wouldn't have written it that way." He said that if Kramer has a problem with the pamphlet he should take it up with Sonner.

Potter said he hadn't read the material when he handed it out yesterday morning and he probably will return it to Sonner today.

Kramer's campaign manager, Lanny Davis, said the piece "crosses the line." If the county's top prosecutor is accusing Kramer of crimes, Davis said, "then he should be prosecuting Kramer." He added that Sonner's pamphlet "is a complete lie."

"Andy Sonner, who was a friend of mine, should be ashamed of himself," Davis said.

"Coming from Lanny Davis, that is worth about 10 cents," said Sonner (D), a Potter supporter who had considered challenging Kramer. Sonner, responsible for investigating and prosecuting criminal matters in Montgomery County, said he was not accusing Kramer of committing any crime.

Sonner, interviewed earlier in the day, wouldn't say whether he is questioning Kramer's honesty or integrity. He wouldn't provide any specific cases of Kramer acting in the interests of his real estate holdings. Kramer is a self-made millionaire who built a vast commerical real estate enterprise from a chain of car washes.

"The piece speaks for itself," Sonner said. Potter said he didn't think the brochure accused Kramer of any crime, just of a bias in favor of development. That was the theme of a news conference Potter held earlier yesterday as he lambasted Kramer for accepting large amounts of money from development interests. He said a review of Kramer's campaign reports showed 80 percent of Kramer's financing came from people associated with development. Potter conceded that the review, done by a citizen political action group supporting his candidacy, is outdated.

Davis said an analysis done by the Kramer campaign showed that between 40 and 49 percent of the nearly $280,000 raised by Kramer has come from development interests. Potter has raised almost $56,000.