Montgomery County Democrats gathered last night for a party intended to heal the wounds of this week's fiercely fought primary, but the speeches of Democratic unity were drowned out by whispers of lingering bitterness.

County Executive Sidney Kramer held out his hand to the man who defeated him, telling Neal Potter, "It's good to be here with you . . . on your moment of victory."

But moments after Kramer and Potter shook hands and posed for pictures, Kramer's wife, Betty Mae, blasted the 75-year-old council member.

"I congratulate you on your victory," she told Potter as she shook his hand. But then she told him that she took "very personally" his campaign attacks on her husband's integrity and the involvement of her family.

"For that, I will never forgive you," she said as onlookers watched in a stunned silence.

Potter listened impassively as she talked, then spoke to her in a soft voice that couldn't be heard by those nearby. He later told reporters that he had simply disagreed with Betty Mae Kramer and that he didn't want to dwell on the encounter.

The scene, during the traditional "kiss-and-make-up party" of the Woman's Suburban Democratic Club, was a reminder of the deep party divisions caused by Potter's challenge. Potter put together a grass-roots campaign that toppled Kramer, the candidate of political establishment, by tapping into voter unhappiness with the county's rapid growth.

Potter enters the Nov. 6 general election as the odds-on favorite, since the county is predominantly Democratic. He faces Republican Albert Ceccone, a Chevy Chase businessman who has run unsuccessfully for Congress and who four years ago lost his party's primary for county executive.

Maryland's two Democratic senators, Barbara A. Mikulski and Paul S. Sarbanes, told the 400 Democrats at Water's Caterers in Rockville that the party needed to be unified in November or it could lose some important state and local contests.

Increasing GOP registration, particularly in Montgomery's growing upper county, gives the Republicans good opportunities to pick up seats in the state legislature and to crack the 20-year domination of the County Council by Democrats.

Lively council campaigns are expected in the Bethesda-Chevy Chase area, where Republican Betty Ann Krahnke faces Democrat Marilyn Goldwater, and in the upper county, where Republican Nancy Dacek opposes Democrat Vickie York.

"We have to support all the Democrats from the top of the ticket down," Kramer told the crowd.

Kramer was greeted with sustained applause at last night's gathering. He flashed the V-for-victory sign and acknowledged that defeat was difficult to accept, but said the tradition of Democrats in Montgomery is to slug it out in the primary and come together to defeat Republicans.

Potter, in his first speech since Tuesday's win, said, "I look forward to a great race and a great four years."

He had words of praise for the man he defeated, noting that he and Kramer had met earlier that day and that the incumbent was arranging for a transition with "grace and efficency."

"I have big shoes to fill and I hope I can do it," Potter said. And, in gentle disagreement with the rebuke he received from Mrs. Kramer, he argued in his speech that his campaign was based on issues and that he had never criticized the way Kramer ran the government.

During the campaign, Potter distributed a flier from State's Attorney Andrew L. Sonner alleging that Kramer placed the interests of his family's real estate business and those of his developer friends ahead of the public.

Meanwhile yesterday, the county board of elections completed its count of absentee votes. Council candidate Gail Ewing maintained her lead to win the race over incumbent Rose Crenca for an at-large position.