Fairfax Republican M. Wayne Huggins turned on his television on election eve four years ago and heard a reporter predict that he had almost no chance of winning election for county sheriff.

Today the 34-year-old former Virginia state trooper is not only sheriff, but he will win a second term to the $55,000-a-year job Nov. 8 without opposition.

"Huggins has done a very good job," said Fairfax Supervisor Sandra Duckworth. "And that's a Democrat saying that about a Republican."

Other Democrats are more grudging. Said one: "The Democrats couldn't get anyone to run against him because he hasn't done anything to screw up."

Perhaps not, but his four years as sheriff have not been without problems. Crowding at the county jail, which his predecessor said was a principal problem, has been eased--but not solved.

And, two weeks ago, Huggins announced that more than $10,000 was missing from two of the jail's bank accounts. A jail trusty is under investigation, and Huggins also said that a senior jail official had taken early retirement and another had been demoted as a result of the shortage.

"If you go to the press first when something happens," said Huggins, "the press seems to react more positively."

Huggins concedes the need for a better image of the office is one of the lessons he learned from the mistakes of his mentor, Sheriff James B. Swinson. The leading Republican vote-getter in Fairfax County for 16 years, Swinson retired in 1979 after criticism and lawsuits over the deaths of three jail inmates. He also was criticized for the alleged misuse of inmates by some of his high-ranking deputies.

Earlier this year, when a man died at a local hospital shortly after being taken from the jail's holding cell for people charged with intoxication, Huggins was quick to call attention to the medical help his staff gave to the man. The sheriff went on to use the incident to complain about the inherent problems of using jails as "drunk tanks."

Huggins hasn't been reluctant to challenge some state officials. He filed suit against the State Department of Corrections for leaving many convicted felons in his county jail and won a court order that forced the state to transfer more than 60 inmates into state prisons.

He successfully sued the State Compensation Board earlier this year for 24 new positions, all to be funded by the state at a cost of $311,212. His department, which is responsible for security in the state courts as well as the jail, has a staff of 250 and an annual operating budget of $8 million.

Huggins, a tall, baby-faced man, describes himself as "just folks," a man who will pull a turkey caller out of his pocket and give demonstrations in the county courthouse cafeteria.

He was Swinson's hand-picked successor. He was named chief deputy under Swinson less than a year and a half before the 1979 election. Once elected, he was criticized by some county officials for appointing Swinson's son-in-law as his chief deputy. He defended the appointment, saying the officer was qualified.

"I knew I was going to run for sheriff the day I came to work here," said Huggins, who began his career in law enforcement as a Secret Service agent and worked seven years as a state trooper, part of that as an undercover investigator.

Huggins, a soft-spoken man with a hint of a drawl, frequently wears a tiny "Jesus" pin on his lapel and says he is a born-again Southern Baptist minus the fanatacism that he says people have come to associate with his beliefs.

Although he expects to spend less than $7,000 on his campaign this year, compared to the $30,000 he spent four years ago, "I take this election very seriously," Huggins said.