Marion Barry, the one-time black activist and District of Columbia school board president, appeared to have easily defeated Republican Arthur A. Fletcher and two others yesterday in the District of Columbia's second election for mayor in more than a century.

Barry, a 42-years old at-large member of the City Council who won a surprise victory in the September Democratic primary, led Fletcher by a margin of more than two to one, based on returns from morning voting in six of the city's eight wards.

Here were the totals from early returns:(TABLE) Marion Barry(COLUMN)21,921(COLUMN)68.0% Arthur A. Fletcher(COLUMN)9,835(COLUMN)30.5% Susan Pennington(COLUMN)339(COLUMN)1.0% Glova E. Scott(COLUMN)161(COLUMN).5%(END TABLE)

Democratic City Council member Arrington Dixon, who faced only minor opposition yesterday, was an easy winner in the race for City Council chairman.

Democrats and incumbents appeared headed for a clear sweep in the races for City Council. At-large council member Hilda Mason of the D.C. Statehood Party was easily reelected. School board member Betty Ann Kane, the Democratic nominee for the second at-large seat on the ballot, also won, making her the first white person to be elected to a citywide council seat.

Democrats David A. Clarke (Ward 1) and Polly Shackleton (Ward 3) were also easily reelected. Two other Democrats, William R. Spaulding (Ward 5) and Nadine P. Winter (Ward 6) took strong leads in the early returns.

The city's most popular politicaian, Walter E. Fauntroy, easily won reelection to his fifth term as the District's nonvoting degate to the House of Representatives. In early returns, Fauntroy was winning more than three-fourths of the vote against three challengers.

Elections officials estimated that about 32,000 people had voted by 1 p.m., indicating that total voter turnout would fall below the 96,000 ballots cast in the 1974 general election.

A smaller turnout had been expected yesterday because in 1974, when the city held its first election in more than a century for mayor and City Council, all 13 council seats as well as the mayor's office were on the ballot.

Some of the most popular figures in the city were running in contested council races in the 1974 election and they brought their own followings to the polls.

By contrast, only seven council contests were considered close.

City election officials reported no major problems at polling places by early evening, even though three different voting systems were in use. This was in contrast to the Sept. 12 primary when there were a variety of problems, including a shortage of ballots at some precincts and the absence of the proper pens to mark ballots at others.

Ever since he won the Democratic primary in September, Barry, who in that race was the self-proclaimed underdog, had been considered the frontrunner in the contest that concluded yesterday.

That status was based primarily on the overwhelming Democratic registration in the city and the fact that Fletcher, a new face in city politics, had not actively campaigned during the Republican primary. Fletcher entered the general election contest with far less money, name recognition and organizational resources than Barry.

In the primary, Barry campaigned as somewhat of an outsider to city government. But in this election he seized on Fletcher's newness, and altered his own campaign posture to that of a veteran of many local struggles. He tried to portray Fletcher as a "stranger"to the city, one who was unfamiliar with problems in the District and uncommitted to solving them. Much of Barry's activity during the general election campaign was concentrated on bringing together the ranks of the city's dominant Democratic party, which had been fractured badly during the primary.

A former local community actvist, school board president and twice-elected member of the City Council, Barry placed his emphasis on creating more jobs, improving educational performance in the city's schools, providing better housing and bettering health care services for senior citizens.

Constantly flailing at Fletcher's claims of vast management experience, Barry accused Fletcher of having "no track record of management even on paper,"and Barry disputed as exaggeration and misrepresentation some of Fletcher's charges.

Barry spent nearly $150,000 during the general election period, much of it to cover debts left over from the primary. His $424,000 overall campaign was the most expensive in city history.

Barry had the support of most of the major interest groups in the city, including organized labor, the majority of the influential black churchmen, the police and firemen's unions, the teacher's union many leading businessmen and gay right activists.

Mayor Walter E. Washington and City Council Chairman Sterling Tucker, Barry's opponents in the primary, gave mostly unenthusiastic endorsement to his general election candidacy, as did Del. Walter E. Fauntroy, who had supported Tucker in the primary.

Barry also had to confront contentions during the general election that his strong support among whites - a significant part of Barry's political base was among liberal, middle-class whites in areas of the city where the white population is growing - made him the "white community's candidate."

The former black community activist responded by saying that the majority of his votes came from blacks.

Fletcher, who had expected a hefty campaign chest stocked by national Republican donors and a race against Washingto in which management skills would be the principal issue, ran against Barry with far fewer resources than he had anticipated.

He raised only $52,000, compared to the $424,000 raised by Barry, who in the final days of the campaign was receiving $5 for every $1 given Fletcher. Fletcher had no television ads and his radio spots began to air only during the final 10 days of the contest.

His low-budget campaign put a heavy emphasis on about half a dozen televised debates, in which he used his forceful and fiery oratory to hammer away at Barry's image as a one-time black militant who ran a controversial self-help program, Pride. Inc.

Fletcher won the support of about two dozen black churchmen, most of whom had backed Washington in the primary. Most of the other major interest groups backed Barry.

By the time the campaign ground into its final two weeks, there was little indication that Fletcher had succeeded in making any significant inroads into the ranks of the Democrats whose crossover votes were essential to his winning the election.

Although Fletcher ran his campaign primarily on what he saw as the need for experienced management and "creative" ideas in city government, in the last days of the campaign his verbal attacks focused on Barry's image.

He accused Barry of "intimidating" "some of his would-be supporters, and cited the alleged intimidation as one reason why he would not reveal a long-awaited list of Democrats supporting his campaign.

Polls taken during the last two weeks of the election showed Fletcher far behind Barry, even with a large number of undecided voters. Fletcher aides insisted, however, that their own surveys had found the race much closer and showed that Fletcher's campaign was gaining momentum.

Yesterday's election was part of the beginning of the second full cycle of local voting under provisions of the Home-Rule Charter of 1974. Four years ago, for the first time in 104 years, the city elected its own mayor and City Council.

Six of those council members stood for reelection in 1976. [Only James E. Coates (D-Ward 8) was defeated then.] Seven more council seats, plus that of the mayor, were up for election yesterday.

Three incumbents (Mayor Washington, City Council Chairman Tucker and at-large Councilman Douglas E. Moore) were defeated in the Sept. 12 primary. One other member of the original elected council, Julius W. Hobson (S-at large) died in office on March 23, 1977.

This year's elections brought a new level of city politics, according to many observers, who felt that during the four years since home rule District politicians had become more sophisticated.

The 1978 campaigns severely strained the ranks of the city's regular Democratic organizations, which was sharply divided by the bitter mayoral primary contest also proved to be an acid political test for the vaunted organization of Fauntroy, which failed to deliver victory to Tucker in the primary.

The unprecedentedly close Democratic primary also again brought to light many shortcomings in the city's votecounting process, which included a 12 day delay and several intermittent snafus before an official winner could be determined.

Fletcher's candidacy in the general election gave the city's Republican party its first impressive candidate in the short history of home rule elections, observers said, adding new vitality to politics here, even though it did not appear to fully challenge the Democratic party's political dominance.