Democrats are taking control of Virginia's local election machinery after almost 16 years of Republican domination.

The change means that as many as 40 GOP registrars statewide, some of whom have been in office for more than a decade, may be ousted from their jobs within the year. In addition, about 130 Republicans sitting on local electoral boards will be replaced by Democrats.

"It's a patronage-type thing for the party in power," said Del. Vincent F. Callahan Jr. (R-Fairfax). "It's one of those political plums that abound in Virginia."

State law mandates that the winning party in the last gubernatorial election be allotted two of the three seats on the electoral boards, which oversee local elections and appoint the registrars of voters. The election of Democratic Gov. Charles S. Robb ensured that control of the boards automatically would have switched to the Democrats over the next year as the terms of GOP board members expired.

But Democrats in the General Assembly this year maneuvered an even faster takeover of local election controls. Lawmakers approved legislation moving the appointment date of registrars from February to March, concurrent with electoral board members' terms.

Under the old law, some electoral boards still could have had a Republican majority when they met next February to select their registrars. But now the registrars won't be appointed until the new Democratic-controlled boards are seated in March.

The new law means Republican-appointed registrars in most counties and cities, including Fairfax and Arlington counties, probably will be replaced next year, according to officials in those counties. Fairfax County's D. Eveland Newman has been in office eight years, and Arlington registrar Peggy H. Wilkinson has been in the job nine years.

The Alexandria electoral board is in the process of selecting an acting registrar to replace Stanford B. Hurst, who is retiring in July after 10 years in office.

The party changeovers have little effect on voters or the people running for office in Northern Virginia, according to Callahan. "It just affects who's running the show," he said.

Callahan and other officials say the party control of the election process has the potential for greater impact in small, rural counties than in larger districts.

And while many consider the appointments "political plums," some of the plums are larger than others.

In Fairfax County, Republican Millard Rappleyea has served for 12 years as secretary or administrator of elections for the electoral board--a full-time position with a $40,000 annual salary. He was replaced last month by Jane Vitray, long-time Democratic Party activist and statewide finance director for Robb's gubernatorial campaign.

Rappleyea held the only full-time electoral board job in the state; all others are part-time. The full-time status was granted in the early 1970s by the General Assembly because of the large size and high voter turnover in the state's largest political jurisdiction.

"I have no quarrel at all that the electoral board be divided between two parties," said Rappleyea. "But I definitely don't think the administrator of elections should also be a board member. It was a serious mistake."

Rappleyea admitted, however, "As long as I was doing it, I didn't fight the system."

But last month, "after 12 years in a career position, I was out because we got a new governor," said Rappleyea, who had been considered a fixture of county government by many residents and politicians.

Rappleyea, now a consultant to the D.C. Board of Elections, said he has applied for an opening as full-time director of the board.

Although Rappleyea was forced to give up the full-time seat on the board, he could have remained in one of the two part-time positions until his term expires next year. But Rappleyea said he resigned when he was hired as a consultant by the District electoral board because "it would have been a conflict of interest, if not illegal."

Two new Democratic members have been appointed to the Fairfax board: Vitray and former Fairfax Sheriff James Swinson, who was named to fill Rappleyea's unexpired membership when he resigned his seat on the board. Republican Nancy Short White remains on the board as chairman.

In Arlington County, Democrat Margo Horner has replaced Republican Ralph Kimble. The two members already seated are William O'Connell, chairman, and Michael Hage, secretary.

In Alexandria, Democrat Donald P. Moore has replaced GOP member Jeff Wainscott. Alfred Swersky is chairman of the board, and Shirley D. Jones is secretary. Both have been on the board several years.

Electoral board members are appointed by circuit court judges in each jurisdiction.