Bob Fletcher, an engineer from Houston, plans to run in Sunday's D.C. Marathon--for his 34th consecutive weekly marathon since he celebrated his 50th birthday last Sept. 1.

"When I turned 50, I decided to take a year off, and I set myself a goal of running in 50 marathons in the next year. It looks like I'm going to beat my goal by two weeks," said Fletcher, in town yesterday to prepare for Sunday's race.

Since September, Fletcher has run marathons in Chicago, Detroit, Kansas City, Birmingham, Atlanta, Dallas and Tulsa, among other cities. Monday, he did the Boston Marathon in 2 hours 55 minutes 37 seconds. "My wife and I have been seeing the country, racing and having a good time," he said.

With just more than 1,000 participants expected, the third annual D.C. Marathon is not in the same league, and probably never will be, as the nation's more prestigious marathons, such as Boston and New York.

But in three years, it has won a small group of followers. Some view it as a convenient alternative to Boston; others see it as a handy local race that provides a running tour of sections of the city they might not otherwise visit.

Both previous men's winners, Will Albers and Robert Hirst, will run this year, as will last year's women's winner, Patricia Howard. But most competitors have no illusions about finishing first, and there may be as many different reasons for joining the race as there are competitors.

Redskin General Manager Bobby Beathard, unable to make Boston this year because of the pressures of the NFL draft Tuesday, says he plans to run Sunday if he can shake a lingering cold and sore throat.

"We got behind in the draft and I couldn't take three days in Boston this year," said Beathard. "I would love to run it, but I'm going to play it by ear. If I do do it, I'm going to run it to finish, but I'm not going to race it."

There is Tom Kurihara, 47, a computer systems analyst from Vienna who has run in all three D.C. Marathons as well as the last four Marine Corps Marathons.

"I think the D.C. Marathon is a good event," said Kurihara, whose 2:51 time last year placed him first in the 40-50-year-old age group. "It's a good scenic tour of the District. The Marine Corps Marathon goes around the monuments, but it doesn't give you a good view of the city."

Similarly, Linda Buttner, 35, a registered nurse from Laurel, is a charter member of the D.C. Marathon participants. "I like doing the first annual marathon and sticking with it," said Buttner, whose three teen-age sons cheer her across the finish line at every marathon she runs in. "It's a low-key type of race. It's for the people, the regular runners."

At 33, Phil Stewart says he's in fine physical condition, capable of finishing a marathon in about 2 1/2 hours. But he had no intention of running in two marathons in the same week. So, this week he had to choose between running in Boston and in the lesser-known marathon here.

"I knew if I went up to Boston and ran my 2:30 I'd come in about 300th," said Stewart, associate publisher of Running Times magazine. "I can do that in Washington and be within sight of the motorcycles. That's what made me decide to forgo Boston for this race. I'm hoping to be up near the front."

Alan Price, 36, of Washington, a race walker who gave up running for walking almost 10 years ago, will do the marathon.

"I do it for the exposure," said Price. "You can have 1,000 people out there running but the people the spectators will remember are those funny people walking. You can tell them from the runners because their bodies are going every which way.

"The runners always laugh when they pass me in the first mile. But then I pass them at the 22nd or 23rd mile. It's like the tortoise and the hare."

Ken Archer, 34, a mathematical statistician with the Bureau of Labor Statistics, will attempt to recapture the prize for wheelchair athletes that he won last year.

"I did the Boston Marathon," said Archer, who finished that race in 2:04, ninth among 23 wheelchair athletes. "I am still recovering from that. My energy supply has been totally drained, and I'm still feeling some pain in my wrists. It will be a difficult race on Sunday and I don't think I'll get a very good time. That course is a tough course and there are some very tough hills on it."

Archer's legs were crushed between two cars in an accident 12 years ago. Over the last few years, he has competed in dozens of races locally and nationally, ranging from 10 kilometers to marathons.

"I like the feeling of being physically fit, and I like to compete," said Archer. He trains at his house by attaching his wheelchair to a treadmill and then doing 45-second sprints followed by 15 seconds rest.

"I listen to my stereo and go for 1 1/2 to two hours continuously every day," said Archer.

Archer is one of at least seven wheelchair competitors registered for Sunday's race. It will begin at 8 a.m. and follow a hilly and circuitous course through all of Washington's eight wards.