Four new candidates have jumped into races for Prince William County supervisor and sheriff in recent days, officials said, complicating the political outlook for several incumbents in November's general election.

Robert K. McBride, of Woodbridge, filed papers Friday declaring himself an independent in the race to unseat Board of County Supervisors Chairman Kathleen K. Seefeldt (D), who also faces a challenge from Republican Sean Connaughton, of Triangle.

Lester Gabriel, of Woodbridge, has been nominated by fellow Republicans as the GOP candidate to oppose Supervisor Hilda M. Barg (D) in the Woodbridge District.

And in two independent bids, former candidate A.D. "Tony" Dominguez, of Dumfries, and former sheriff's deputy Todd L. McEwen, of Nokesville, each filed to oppose first-term Sheriff E. Lee Stoffregen III (D) in November.

The flurry of new candidacies came amid final campaigning and voting in yesterday's primaries, which included five intraparty contests in Prince William. [Story in Metro section.] Taken together, the primary and the recent filings will determine the final slate of candidates to appear on the November ballot.

The entry of Gabriel in the Woodbridge race means that three of Prince William's eight supervisor positions are contested. The at-large chairman and Gainesville supervisor positions have had declared opponents for months.

And the entries of Dominguez and McEwen mean that Prince William's best-funded local politician suddenly faces opposition from two fronts. Stoffregen has amassed a campaign war chest eclipsing that of any other Prince William politician, with more than $130,000 on hand at the beginning of the year.

McEwen, who now runs a private company that serves legal documents, said he was a 16-year veteran of the Sheriff's Department when he supported a Stoffregen opponent in the 1995 election. He said he was pushed out of the department soon after.

"I was told that I wouldn't be re-sworn" as an officer, McEwen said. "I wasn't forced to quit officially, but I guess you could establish it as the same thing."

McEwen, 40, said that he would work to improve efficiency in the sheriff's office and that he isn't daunted by Stoffregen's financial resources.

"This race will be about credibility," he said.

The other new candidates could not be reached for comment yesterday.