The party held in honor of State Sen. B. W. Mike Donovan was planned as a standard scene from the book of Prince George's County politics. Donovan, a white conservative who represents the new 25th District, paused amid the festivities to review his accomplishments with a group of black constituents from largo.

"He started off with something like, 'I have worked hard to ensure welfare benefits for AFDC (aid to Familities With Dependent Children) recipients,'" according to a black civic activist who attended the party last March. ". . . He was talking to this middle- classclass Kettering crowd," repeated the activist, his voice rising, "and he says. 'I've worked hard for AFDC benefits!' I mean, he doesn't know who these people are!"

These people are from Largo, Kettering, and parts of District Heights, among the truly integrated communities in the county, and home to almost equal numbers of black and white middle-income residents. But those areas, most of them included in the 6th Councilmanic District and Donovan's 25th Legislative District, have no black elected officials to represent them in the county council or at the Legislature.

In part because they say they are tired of politicians who don't even know when they are making the wrong speech, 10 black candidates are seeking nomination Tuesday to some of the 21 available elective offices. Political observers of both races say the results of those challenges represent an important test of black voter strength.

"Certainly it's an insult to the majority of the district to have an all-white delegation in this day and age," said Horace Hillsman, 43, and one of four black candidates, along with one white challeger, seeking to unseat Donovan.

Donovan, 62, has represented the area as a delegate or senator since 1966. His home community of District Heights, established in the 1930s, was a predominately white community when he moved there in 1957. Many of the black candidates say his vote against giving D. C. full voting representation in Congress is a metaphor for his insensitivity to black concerns, though he says the bill had "constitutional problems."

The newly reapportioned Legislative district, which stretches to the District line and takes in District Heights, Morningside, Largo and parts of Suitland and Kettering, is about 60 percent black. The new councilmanic district is about half black.

"It's an ideal place," said a 37-year-old white Kettering homeowner. "Most of the families are stable, our kids have friends, Kettering is basically integrated. It's neighborly."

"Nobody looks at color schemes here," said JoAnn Bell, 44, a white housewife and school board member from District Heights who is a challenger for the 6th District council seat. She bristled at a question of whether whites in her area would vote for a black candidate. "You're creating an issue where it doesn't exist."

But many black residents and candidates take a less sanquine view of the state of race relations in a 40 percent black county with an history of racial discord.

While he feels most area whites are open-minded, Albert R. Wynn, 31, a black Lawyer running for a House of Delegates seat on a ticket with Donovan, admits he had "apprehensions" about door- knocking in some areas -- "which I'm glad to say were not realized," he added quickly.

Still, a single incident, in which a a white Morningside homeowner sicked a dog on one of Wynn's black volunteers, was exaggerated in retelling until it was told that Wynn had been repeatedly attacked by angry dogs and bigots.

Some political observers wonder whether in fighting and the sheer number of blacks running will so divide the potential "black" vote that none will be nominated on Tuesday. If that happens, views differ over the effect.

"I see the campaign as having a positive effect on getting blacks involved either way," said Jerry Eileen Perry, 37, a Largo woman who is running for a delegate seat. "If I don't win I'll be back, trying to keep people involved, keep them from going back into their little hole."

But Senate candidate Hillsman said, "I am afraid that blacks are going to say, 'government just isn't for us, it just doesn't work like it shoud.'"