Two weeks ago, Isiah Leggett, Montgomery County's only black council member, passed out campaign literature to residents along Western Avenue, a street that divides the county from the District.

As he approached one white resident with material in hand, the man called out that he was a Montgomery County voter, not a District resident. The assumption was that because Leggett is black, he was a city candidate who had mistakenly wandered into the wrong jurisdiction to campaign.

The incident illustrates the uphill battle facing many minority candidates in Montgomery as they try to break into an exclusive club of elected officials. Leggett is the lone black elected official even though the minority community of African Americans, Hispanics, Asians and other ethnic groups makes up more than 20 percent of the population.

The 1990 campaign will do little to change the status quo. There are three minorities running for school board this year -- a black man, a Hispanic woman and a Chinese American man -- and three running for the House of Delegates, an Indian, a Latino and a black man.

"As a whole, they {white politicians} don't feel we are an important group or there are enough of us to make it a concern," said Janice A. Burton, president of the county chapter of the National Coalition of 100 Black Women.

One result of increasing frustration over the lack of minority elected officials in the heavily Democratic Montgomery is a growing number of minorities who are gravitating toward the county Republican Party, which has black, Hispanic, Asian and Indian Republican clubs.

Unlike their counterparts in Prince George's County, where blacks have made steady inroads into elected office during the last 15 years, Montgomery County blacks and other minorities have remained largely outside of the electoral process, some working behind the scenes but many not participating at any level outside of the voting booths.

There are essential differences between the minority communities of Prince George's and Montgomery. Prince George's is about evenly split between blacks and whites, but even when its black population hovered at 20 percent, there were large concentrations of minorities in communities such as Glenarden, Fairmount Heights and later Capitol Heights. Blacks were able to build a base from which a bid for higher office could be launched.

In Montgomery, which has one of the most affluent and highly educated black communities in the nation and where the Hispanic community is large and entrenched, minorities are spread out over the 495-square-mile county. A survey by the NAACP four years ago found that none of the county's senatorial districts has a black vote of more than 18 percent.

"There is no real one part of the county where there is a quote-unquote black area," said J. Bradford Coker, president of Mason-Dixon Opinion Research in Columbia, which has done polling and demographic studies in the county.

There are other factors as well. In the black community, Leggett and others pointed out, a sense of defeatism has set in. Since 1980, several blacks have run for everything from sheriff to school board to County Council and all except two have lost badly. Leggett said he won only because he began running a year and a half before the primary and had time to build name recognition in white, rural and conservative areas of the county. The other, Odessa Shannon, was elected to the school board in 1982.

"You have to go where the votes are. It doesn't make any sense to spend 80 percent of your time chasing 20 percent of the vote," Leggett said.

In the Hispanic community, activists said, factionalism, newness to the community and a lack of political acumen have affected its ability to elect one of its own. The Montgomery County Hispanic Alliance was formed in January to help change that.

"It's amazing how many people will say {they've} lived here 20 years, sent {their} kids through school and have not taken a part in community affairs," said Ana Sol Gutierrez, 48, who came here from El Salvador when she was 3 and who is running for school board.

Political observers say the impact could change in 1994. "As the population of minorities grow, they will become more and more of a factor not only as it relates to running for office but in affecting many races," said County Executive Sidney Kramer.