Senior citizens were munching on tuna sandwiches and bean salad when mayoral candidate Charlene Drew Jarvis popped into the Greater Southeast Senior Center this week. As the 50 elderly people continued eating their lunch, the Ward 4 council member strode to the middle of the room and launched her campaign pitch:

"The Barry administration really did expand senior citizen programs, don't you agree with that?" Jarvis asked. The group responded with a collective yes. Many nodded their heads for emphasis.

"I want you to know I am going to continue those programs for seniors," said Jarvis, who concluded by asking the group to support her in tomorrow's Democratic primary.

The city's older voters are being buffeted with appeals in the final days of this campaign.

Traditionally, they have been an important component in Mayor Marion Barry's support. But Barry is not in this race. And now, the five Democrats vying to succeed him are scrambling to corral this key bloc of voters.

A recent Washington Post poll found that none of the five was the overwhelming favorite of voters aged 60 and over.

Senior centers, senior housing projects and nursing homes -- where clusters of elderly people can be found -- have therefore become a major campaign battleground as candidates try to tap into the repository of senior voters.

D.C. Del. Walter E. Fauntroy went looking for votes at two nursing homes in one day last week. He visited Grant Park Care Center in Northeast on Thursday morning and Stoddard Baptist Home in Northwest that afternoon.

D.C. Council Chairman David A. Clarke, who stops at least once a day at a senior center, spoke Saturday at a rally at NCBA Estates, a senior citizen housing project in Northwest. A special mailing headlined "As Mayor, Dave Clarke Can Do More for Senior Citizens" is being sent to about 30,000 older voters.

Candidate Sharon Pratt Dixon delivered a campaign address on Wednesday to the residents of Thomas House, a downtown retirement complex.

And council member John Ray (At Large) has enlisted the assistance of volunteer organizer Concha Johnson, director of the city-funded Senior Citizens Counseling & Delivery Services, a Southeast service agency for the elderly.

"Senior citizens are reliable voters," said Ray press secretary Margaret Gentry. "And you don't find any group more committed or more dedicated to the person they support."

About one-fifth of the 233,313 registered Democrats in the District are over 60 years of age, and many of these voters are eligible for the government-funded programs that provide the elderly with meals, housing, transportation and health care.

In an interview this summer, Barry gave high marks to these services, which he personally has championed since the mid-1970s, when he co-sponsored legislation to create the D.C. Office on Aging.

"Senior citizen services I give A-plus, A-plus, plus, plus," he said. "That's why I have a lot of support among seniors."

Jarvis has had the support of the mayor's wife, Effi, in trying to attract Barry's senior citizen backers.

Effi Barry has accompanied Jarvis to several senior citizen centers in recent days, reminding senior citizens there of her husband's emphasis on caring for the needs of senior citizens and telling them that she is endorsing Jarvis because she is confident that a Jarvis administration would have as great a concern for them as the Barry administration.

But the Washington Post survey also found older voters tended as a group to be less patient with the D.C. government bureaucracy and more inclined to want the size of that work force reduced. Older voters also want the District's next mayor to clean up the city's image, the poll found.

Elderly voters, meanwhile, are flexing their political muscle.

The Regency House Seniors Action Group, unhappy with the "slum-like state" of their senior citizen apartment house at 5201 Connecticut Ave. NW, "wanted to take advantage of the fact that the elections were coming up," said organizer Kenneth A. Brown.

The group invited candidates to an Aug. 13 forum to answer questions about the city's failure to make needed repairs, Brown said, and about 20 candidates, including most of the mayoral candidates, attended.

Since then, Roland L. Turpin, director of the city's Department of Public and Assisted Housing, has come to inspect Regency House, and "they have sent people in to plaster holes in the walls," Brown said.

"Nothing like this has happened here before," Brown said.

Senior citizen groups, while trying to persuade candidates to commit themselves to addressing seniors' issues, have been slow to show their support.

The Gray Panthers of Washington, D.C., sponsored an Aug. 25 forum at St. Mary's Court, a senior residence in Northwest. But the 3 1/2-hour session ended without any endorsements.

"Each person will decide for herself or himself," said forum organizer Ethel Weisser.

But some haven't decided whom to back.

"I find it very difficult to choose a candidate for mayor," said Sue Whitman, 79, a Northwest resident and a community activist who has worked for improvements in home care for senior citizens.

Whitman said she wanted a mayor with vision for the larger problems of the city but who also can be effective and carry out programs.

"All the candidates claim they are for senior citizens," Whitman said, "but the issues are much larger than that. There is a financial crisis in the city, there is a crime issue, an education issue. It is not just the old people we have to be concerned about. The new mayor needs to be someone with the vision to put this back together."