In the first contested election for Fairfax County sheriff in a decade, Acting Sheriff Carl Peed, a Republican, is battling challenges by Democrat Richard Singleton, a retired Army colonel and independent Clarence A. Robinson Sr., a longtime pastor in Northern Virginia.

The candidates and political observers say the race, while low-key, may be close, at least between Peed and Singleton.

The winner of a Nov. 6 special election will serve the rest of M. Wayne Huggins's four-year term. Huggins resigned in February to become the director of the National Institute of Corrections. Another election for sheriff is set for 1991.

The sheriff is responsible for running the county's 589-bed jail, which averaged 1,000 inmates last year. The office is also responsible for maintaining courthouse security, administering a $22 million budget and overseeing 433 employees.

The candidates, none of whom has run for elected office before, say the only issue in the race is who is most qualified for the job.

Peed, 43, who has worked in the sheriff's office 16 years and was chief deputy under Huggins 10 years, is campaigning on the record of his experience. He says during those years he helped establish several award-winning programs in the jail. While Peed was chief deputy, he says, the jail was accredited twice by the American Correctional Association and five times by the American Medical Association.

"This is what the race is all about -- accreditation and experience," Peed said recently.

Peed grew up in Hamlet, N.C., where his father worked as a sheriff's deputy and was once shot in the stomach as he tried to destroy a moonshine still.

After graduating from college and serving in the Army, Peed came to Fairfax in 1974 and married Charlotte Swinson, the daughter of James Swinson, a longtime sheriff in Fairfax.

Peed joined the Sheriff's Department where he swiftly rose through the ranks. Six years after entering the department, he was named chief deputy.

Democrats say that accomplishments at the jail came under the leadership of Huggins, not Peed.

"I don't think there is a need to knock Carl Peed," said Harris Miller, chairman of the Fairfax County Democratic Committee. "He was a good number two. By accident of history he ended up number one. If you compare the experience of Singleton, you're talking about a guy who is colonel versus someone who is a major."

Richard Singleton, 55, a retired Army colonel, cites his 30 years in Army law enforcement and the last two years as warden of the Maryland House of Corrections in Jessup as his qualifications to be sheriff.

Stuart Comstock-Gay, director of the American Civil Liberties Union in Maryland, gives Singleton high marks for the Jessup job. "In his relatively brief tenure, a lot of things improved, particularly in terms of the physical plant," he said.

Singleton, who lives in Burke, said he left the job after 14 months to run for sheriff because the Fairfax jail is closer to home and he wants to serve in Fairfax County.

During his three decades in the Army, Singleton was director of the 1,000-inmate Army correctional facility at Fort Riley, Kan.; he commanded a military police battalion at Fort Dix, N.J., and served as a military police officer and provost marshal in several overseas posts. He retired from the Army in February 1989 after five years in the Office of the Inspector General, where he oversaw the Army's fraud, waste and abuse-prevention program.

Singleton is a graduate of South Carolina State College and has a master's degree in public administration.

Singleton said the Fairfax jail, in spite of its national recognition, has its problems. "When my opponent gets up and reads off all these accomplishments, it takes a guy with 30 years of experience to recognize the holes," he said during a recent interview.

He wants to increase courthouse security with metal detectors, increase drug programs for inmates, put more prisoners to work and set up a boot camp for young offenders.

If Singleton is elected, he would be the first black elected to a countywide office in Fairfax and the first Democrat to hold the office in almost 30 years.

Clarence A. Robinson Sr., 63, said he decided to run as an independent in the race after the county's Democratic Party refused to endorse him. Robinson, a civil rights activist and former president of the local branch of the NAACP, said he decided to run because he thinks the people of Fairfax County want a change.

"I'm not a part of the good old buddy system," he said. "I don't believe in nepotism. I haven't been sheltered in a military society. I've been out in the cold war all my life."

Robinson, who lives in McLean, has been pastor of Mount Calvary Baptist Church, and is now pastor of Macedonia Baptist Church in Arlington.

"I'm going to win this election, incidentally," he said.