Fairfax County’s election slate is coming into focus, and this much is clear: It will be a very good year for people who earn a living making campaign signs.

Party-sponsored candidates had until June 15 to file to run in the Aug. 23 primaries, and with every state and local office in Fairfax County except county clerk up for grabs, the stakes are high.

Republicans hope to wrest control of the Virginia Senate with several key races in Fairfax and other Northern Virginia districts. Democrats are fighting to hang on, casting themselves as the lone bulwark against GOP dominance of state government.

Democrats also hope to keep their grip on Virginia’s most populous and economically powerful jurisdiction, and perhaps even build on their majority by taking back a seat on the Fairfax County Board of Supervisors from a Republican in the Braddock District.

Republicans hope to keep the Braddock seat in their column and increase their numbers on the board, but they like their odds even better in what is shaping up to be a spirited and wide-open fight for the Fairfax County School Board.

“There is a ton of anger out there about how the School Board and the superintendent are running the schools,” said Anthony Bedell, chairman of the Fairfax County Republican Committee.

All 10 incumbents on the Board of Supervisors — seven Democrats, including chairman Sharon Bulova, and three Republicans — have filed for reelection in districts that changed only minimally because of redistricting.

In elections for law enforcement offices, two Republicans, Harold “Wes” Kammerer and William A. Cooper III, will face off in the primary to determine who will challenge incumbent Sheriff Stan G. Barry (D). Commonwealth’s Attorney Raymond F. Morrogh (D) will run unopposed.

Some themes have already emerged. Several Senate districts in Fairfax, including those held by first-term Democratic Sens. George L. Barker and David W. Marsden, are expected to be among the state’s key battlegrounds as the GOP tries to overcome the Democrats’ 22-to-18 lead. So is the seat held by Sen. Linda T. “Toddy” Puller, as two Republicans, ousted state GOP leader Jeff Frederick and Prince William County businessman Tito Munoz, have filed to challenge the Democrat.

Two additional Senate seats in Northern Virginia have opened up through the retirements of Sens. Patricia S. Ticer (D-Alexandria) and Mary Margaret Whipple (D-Arlington).

Although the Republican-controlled House of Delegates has a formidable majority, both parties are watching the match between incumbent Del. David B. Albo (R) and Democratic challenger Jack Dobbyn in a Fairfax district that has been drifting toward Democrats. Another closely watched race involves Del. Barbara J. Comstock, a McLean Republican who is running for a second term, and Democratic challenger Pamela B. Danner.

In the Board of Supervisors races, the Braddock District will be watched as a bellwether, as Democrats hope to retake the seat that Republican supervisor John C. Cook won after Bulova, who represented Braddock for 21 years, became chairman.

Two Democrats — Janet S. Oleszek, a former School Board member who nearly defeated then-Sen. Ken Cuccinelli II (R) four years ago, and Chris Wade, a newcomer with endorsements from Bulova and others — will face off in the primary.

As a member of the board’s Republican trio, Cook has voted against budgets that includes effective tax increases, and he has been a skeptic of spending on affordable housing. In an interview, Cook said he believes that voters will reelect him because of his record of handling constituents’ needs.

“My theme is ‘taking care of our neighbors,’ ” Cook said.

With half of the School Board’s incumbents retiring and a series of controversies surrounding Virginia’s largest school district, there is keen attention on that board’s races. Democrats say people are following the campaign only because six members are retiring. But Republicans say many people are unhappy with the board and Superintendent Jack D. Dale because of controversies including a zero-tolerance discipline policy, the imposition of fees for playing team sports and the closing of Clifton Elementary School.

Republicans say their 43 candidates make up one of the most inclusive tickets ever offered by the GOP in Fairfax, with more women and minorities than ever. Democrats argue that the Republican candidates are more extreme than ever. Democrats say voters would be wise not to disturb a team whose pragmatic management has enabled Northern Virginia to weather the economic recession better than its peers.

“I think we have a very positive story to tell,” said Bulova, who will face Republican Michael “Spike” Williams of Herndon. An independent candidate, A. Will Radle, of the county’s Alexandria section, has also filed to challenge her.

Rex Simmons, who chairs the Fairfax County Democratic Committee, said the Republican slate has been infected with the extreme ideology of the tea party movement.

“The other side is against government, period. That’s all they want to do is tear government down,” Simmons said.

But Bedell said the GOP plans to follow the strategy that handed victory to Gov. Robert F. McDonnell (R): emphasizing efficiency over ideology. That means focusing on economic growth, fixing transportation problems and holding down taxes, Bedell said.

“I think people are more and more given to voting for Republicans in Fairfax County because we’re the party of ideas and solutions,” he said.

“Just because Sharon Bulova’s been in office 20-plus years doesn’t really mean she’s doing a good job,” Bedell said, adding that it is like “being in your own bubble; you breathe your own fumes.”