The Washington County Sheriff's Department's second-highest ranking officer will be taking over for his boss.
Col. Douglas W. Mullendore beat out Republican challenger Rich Poffenberger, a Maryland State Police corporal, in Tuesday's general election.
Mullendore's boss, Charles Mades, has been sheriff for 20 years.
With all 50 precincts reporting, Mullendore led Poffenberger by 21,533 votes to 14,720, according to unofficial results.
According to Washington County Board of Elections figures, 4,037 absentee ballots were distributed, and 3,550 had been returned as of Tuesday evening.
"If it goes as stands, I congratulate Doug on a well-ran campaign," said Poffenberger, who thanked his supporters.
"We're going to continue to work on the gang and the drug problem in Washington County," Mullendore said late Tuesday. "The first thing that we need to get through, of course, is the budget process, and that comes up in December."