Fairfax County voters appeared ready to give their current Board of Supervisors another four years as early returns pointed toward victory for all incumbents.

In the tightest and most closely watched battle, Supervisor John C. Cook — a Republican who had won the swing Braddock District in a 2009 special election after more than 20 years of Democratic control — eked out a victory over Democratic challenger Janet S. Oleszek with all precincts counted, according to late unofficial results.

With three of 10 supervisors running unopposed and others lining up against nominal opposition, the supervisors’ campaign this year was overshadowed by intense interest in Fairfax School Board races and the statewide battle for control of the Virginia Senate. Yet the election still represented a referendum of sorts on the direction of Virginia’s biggest jurisdiction and one of the wealthiest suburbs in the country.

“I consider this an affirmation that the Fairfax County Board of Supervisors has been a responsible steward,” said Board Chairman Sharon S. Bulova (D) who appeared headed toward a commanding victory with 80 percent of the vote tallied. “I’m also pleased that my colleagues were reelected by such comfortable margins.”

Bulova said her first order of business would be to hold a retreat among the supervisors with at least one day devoted to working with the county’s new school board.

Bulova and fellow Democrats in the 7-to-3 majority had urged voters to reelect a team that guided the county through the worst recession in generations with limited cuts in services and relatively steady rates of taxation. They ran on excellent schools and a business-friendly environment that has lured several Fortune 500 companies.

Michael J. “Spike” Williams, Bulova’s challenger for the chairmanship, led the GOP in arguing that the board — under Bulova and her predecessor, Rep. Gerald E. Connolly (D-Va.) — enacted policies that have squeezed middle-class taxpayers.

“My big overarching message is that we need a new form of leadership in Fairfax County,” Williams said Tuesday before the polls closed. Williams and other Republicans said that besides doubling real estate taxes from 2000 to 2007, the Democratic-led board has devoted too many resources to nonessential programs — such as affordable housing — and building a bureaucracy at taxpayers’ expense.

“My expectation is they would see their tax bill go down” with new leaders, Williams said.

But Bulova noted that the true effective tax on many homes — including Williams’s in Herndon — had fallen during her tenure. Tax records show that Williams’s tax dropped from $6,918 in 2005 to $5,484 last year.

At Lake Braddock High School, voters from two precincts — Signal Hill and Lake Braddock — voted in style, accompanied by the aroma of fresh coffee wafting from a refreshment stand and classical music from a high school string quartet.

Bob Hicks, Republican precinct captain for Signal Hill and Lake Braddock, said turnout was reasonably strong in the swing district because of the closely watched matchup between Cook and Oleszek.

“That’s bringing a lot of people out,” Hicks said. “I think the contested races for state Senate seats are bringing people out. And there’s pretty strong dislike for the current School Board that’s bringing people out.”

Jonathan Ottke, Lake Braddock’s Democratic precinct captain, agreed.

“It seems to me that both bases are kind of excited about voting this year,” Ottke said.

Braddock is considered a bellwether for Fairfax, and this year’s matchup pitted Cook, the first Republican to hold the seat in more than two decades, against Oleszek, who had previously served on the School Board. Carey Campbell, chairman of the Independent Greens of Virginia, ran as an independent.

In Dranesville, Dennis Husch (R), a former Herndon Town Council member, challenged Supervisor John W. Foust (D) in a district that usually favors Republicans in an off-year. Husch criticized Foust for what he called his cozy relationship with developers, especially in Tysons Corner, where the public could pay 58 percent of infrastructure costs. Foust has said that the figure is exaggerated because it doesn’t account for private funding for Metro’s extension. Foust was well ahead in early returns.

In the Sully District, newcomer Shahid Malik (D) challenged Supervisor Michael R. Frey (R). Malik, who served as president of the Ahmadiyya Muslim Community’s Northern Virginia mosque in Herndon, said that Frey had lost touch with his constituents and given too much sway to developers. Frey, who has served as the district’s supervisor since the district’s creation after the 1990 Census, said he had the requisite experience to manage the county’s complex issues. Frey was far in front of Malik in early returns.

In the Mason District, M. David Feld, an engineer, ran as a Republican against Supervisor Penelope A. Gross (D). Feld, former president of the Lake Barcroft Association, disagreed with Gross’s support for trolley service and extending Metrorail to Dulles International Airport.

Gross, who was first elected in 1995, said that experience counts, and she touted her work on revitalizing the inner suburb with projects in Annandale and Baileys Crossroads. Gross appeared to be cruising to reelection in early returns.

Early returns suggested that Supervisor Linda Q. Smyth (D-Providence) also appeared to be on her way to reelection against Chris Grisafe, a former Coast Guard member who recently moved to the district and ran as a Republican.

Supervisor Gerald W. Hyland (D-Mount Vernon) was well ahead of G. Gail Parker, vice chairman of the Independent Greens, who ran as an independent.

Supervisors Catherine M. Hudgins (D-Hunter Mill), Patrick S. Herrity (R-Springfield) and Jeffrey C. McKay (D-Lee) ran unopposed.