D.C. Council member John Ray, encountering fund-raising difficulties in his campaign for mayor, has laid off some members of his campaign staff and reduced the salaries of others.

Two other major candidates in the race, council members Betty Ann Kane (D-At Large) and Charlene Drew Jarvis (D-Ward 4), also said they have encountered problems raising funds.

And while campaign aides for the other major challenger, former Carter administration cabinet member Patricia Roberts Harris, report that fund raising has gone well, they acknowledge that it has proceeded at a slower pace than they had expected.

Thus far, only Mayor Marion Barry's campaign has reported no lag or difficulty in raising money.

Ray said last week he has raised about $50,000 in contributions since March 10 but in small amounts, $50 and $100 contributions, which he says have been hard to come by. The $1,000 and $2,000 contributions that were regularly sprinkled among Ray's early contributions are rare now. Ray had raised $113,377 last year and another $86,974 in January.

Ray said he has laid off his campaign office manager, Vanessa Minter, receptionist Audrey Washington, data processor and general assistant Luvinia Turk and secretary Jaye Scott.

He also has asked campaign manager Burtell M. Jefferson, assistant campaign manager Chuck Esters and press secretary Margaret Gentry to take a 15 percent pay cut, he said.

Ray said that despite the layoffs and pay reductions, the size of his monthly payroll will remain about the same because he has hired two secretaries and started a phone bank of 20 part-time employes to contact city residents and seek campaign support.

"We're having to push to get any money right now," Ray said, "but we're nowhere near in so much trouble that we're thinking of dropping out now . . . People who have money to give are waiting to see who will be most likely to win."

Ray has spent most of his money so far on radio and other advertising. An aide called the response to the ads "a disappointment," but said the campaign is optimistic about new tactics like the phone bank.

"There are some big contributors . . . that have money and have yet to give," Ray said. "Where they end up going is crucial for me, for Pat Harris, and for Betty Ann Kane . I'd have to say right now Pat Harris and Marion Barry have the best chance of getting that money."

In fact, a number of financial heavyweights did announce support for Barry or Harris late last week. Oliver T. Carr, one of the city's major developers, announced that he would be cochairman of Harris' finance committee with Flaxie Pinkett, a well-known realtor. And Delano Lewis, cochairman of Barry's finance committee, announced that Woodward & Lothrop president Edwin Hoffman and lawyer R. Robert Linowes will give a cocktail party fund-raiser for Barry on May 26.

Money problems have already taken two major candidates out of contention for the Democratic nomination in the Sept. 14 primary.

Council member John A. Wilson (D-Ward 2), saying he could not raise enough money to sustain his effort, dropped out two weeks ago. Former council chairman Sterling Tucker, who finished second to Barry by only 1,500 votes in the 1978 primary, decided in February not to enter the race at all because of campaign fund-raising difficulties.

Barry, meanwhile, has already raised about $600,000, more than the $500,000 some of the challengers are hoping to have by the end of the election.

At what is still a relatively early point in the campaign, the fund raising is important to the candidates, especially the challengers, for financing advertising campaigns to build name recognition and image. Candidates also use this early money to staff their campaign offices, which often become the cornerstones of full-fledged campaign organizations.

"We are putting a push on to get more money now," said Kane, who wants to begin costly television advertising next month. "We've had money when we needed it up to now, but it would be fair to say we're not getting the response we would like from the business community."

As a result, Kane, who has raised about $180,000 for her campaign so far and has $75,000 on hand, is resorting to raising money through smaller contributions ($100-$200 each) at household fund-raisers.

Jarvis has raised more than $20,000 and has pledges for another $30,000 by late May, according to Woodrow Boggs, her campaign manager. Boggs said he hopes to raise $250,000 for the campaign, one-half of what other candidates are shooting for as a total fund-raising goal.

Boggs said Jarvis' main hurdle in fund raising at the moment is that many businessmen and candidates expect her to drop out of the race soon. He said the campaign expects to gain momentum when Jarvis picks up her petitions for the primary on May 14.

All candidates for the Democratic nomination must file the petitions by July 7 with 2,000 valid signatures in order to be on the ballot.

"No question we need some money," Boggs said. "But you've got to remember that money isn't everything. If money was all there was to it, Sterling Tucker who was the top fund-raiser in the 1978 primary would be mayor today. In a town this small if you get some good press and use what money you have well you can match up with the mayor, and I expect he'll get a million dollars."

Harris has not done as well at raising money as her opponents had expected.

Sharon Pratt Dixon, the director of Harris' campaign, said last week that Harris has raised more than $100,000 in the seven weeks since March 10, when the candidate indicated that she had raised $80,000.

Dixon said Harris has planned fund-raisers almost every night for the month of May in order to meet a campaign goal of raising another $100,000 in order to have $300,000 by June 10, the next reporting date.

The others in the Democratic primary--physician Morris Harper, publisher Dennis Sobin and artist Richard Jackson--have raised far less money than the major candidates.