Fairfax County Supervisor Jeff C. McKay (D-Lee), left, is the Democratic nominee to chair the Board of Supervisors. He faces Republican Joe Galdo in November. (Evan Cantwell, Galdo campaign)

The results were barely in from Fairfax County’s Democratic primary last week when Republican Joe Galdo reminded voters that there are more battles to be waged for control over Virginia’s most populous jurisdiction.

“For those who want change in Fairfax County, who want innovative but common sense, pragmatic solutions to the county’s problems, I am the only choice,” Galdo tweeted Tuesday night.

In other words, don’t just assume that Democratic nominee Jeff C. McKay is going to be elected chair of the Board of Supervisors in November, when fully half the board seats will be open and significant change is therefore guaranteed.

Fairfax has become a solidly blue Washington suburb, with just two Republicans on the 10-member board, down from six seats in the early 1990s.

But after Democratic calls during the primary to increase spending for schools, affordable housing and environmental regulation, Galdo, four other Republicans and one independent candidate are hoping to prevail with a focus on controlling spending and avoiding groupthink.

“Balance is good for all of our citizens,” said Supervisor Pat Herrity (R-Springfield), who is seeking a fourth term and faces a Democratic challenger in a changing district that has backed Democrats — including Hillary Clinton, Gov. Ralph Northam and Sen. Tim Kaine — in recent elections. “You don’t want 100 percent Democrat, or 100 percent Republican. You need some balance. I think you get to better answers.”

The other Republican on the board, Supervisor John C. Cook (Braddock) is not seeking reelection.

Galdo, 73, launched his campaign to replace outgoing board chair Sharon Bulova (D-At Large) with a President Trump-like proclamation that he would “Make Fairfax Safe Again” by fighting the smattering of gang-related violence in the county of 1.1 million residents.

Since then, the former Defense Department technology intelligence analyst has focused on more pragmatic issues, such as scaling down development in areas like Tysons and Reston, which he says is killing the county’s tranquil suburban roots.

“Our infrastructure — meaning our roads, our public transportation and our schools — are about a decade behind with the growth that the county is experiencing because of this focus on development and bringing a new population into the county,” Galdo said. “And the people who are already here are being left behind.”

McKay, 43, who has represented the Lee district on the board for 11 years, called that viewpoint “very simplistic.” He said it ignores measures in place to control growth and implies the county’s increasing diversity is harmful.

“We have to grow our commercial tax base if we are going to generate the kind of revenue that’s necessary to pay for our services without having to always increase taxes on homeowners,” McKay said. “You’re not going to solve our affordable housing problem in Fairfax County without growth.”

James R. Walkinshaw, Democratic candidate for Braddock district supervisor in Fairfax County. (Walkinshaw campaign)

Jason Remer, Republican candidate for Braddock district supervisor in Fairfax County. (Remer campaign)

One of the more competitive district races will probably be for the seat in the Braddock area, where Cook was reelected by six points in 2015 and voters since then have backed Clinton, Northam and Kaine by double digits.

Democrat James Walkinshaw, chief of staff to Rep. Gerald E. Connolly (D-Fairfax), won Tuesday’s primary, and is facing moderate Republican Jason Remer, an engineer who focuses on renewable energy, and accountant Carey C. Campbell, a member of the Green Party who is running as an independent.

Carey Campbell, independent candidate for Braddock district supervisor in Fairfax County. (Campbell campaign)

All three want to improve transportation options in the area, particularly at the often-crowded Virginia Railway Express stations in Burke. Walkinshaw, 36, predicted that at least some of the estimated 25,000 people who will work at Amazon’s new headquarters in nearby Crystal City will want to live along the commuter rail line.

“We’ve got to make sure that we have the capacity in terms of parking facilities, in terms of rail cars, in terms of station platforms to accommodate that and get more folks off the road,” he said.

Walkinshaw also said he wants to bring more affordable housing to the Fairfax Center area and get the county to work harder on reducing its carbon emissions.

Remer, 60, agreed those goals are vital and said he has the technical expertise to carry out much of what needs to be done in Fairfax.

“If I win, I’ll be the only engineer on the board,” Remer said, noting he has worked on streamlining plans at renewable energy plants. “With a $4.5 billion budget, I think the time has come to have someone who actually understands many of these major infrastructure projects.”

Campbell, 62, said he wants to cut subsidies for businesses relying on fossil fuels and add more bike lanes to local roads.

In the mostly Democratic Providence district, Supervisor Linda Q. Smyth (D) is stepping down. Democrat Dalia Palchik, a member of the Fairfax County Board of Education, and Republican Paul Bolon, a retired manager at the federal Occupational Safety and Health Administration, are vying to replace her.

Both say they want to pursue smarter transportation options in the area that includes Tysons and Merrifield. Palchik, 35, who would be the county’s first Latina board member, also says she wants to raise teachers’ pay and build more classrooms.

“I’m running to help modernize schools, bring thoughtful transit-oriented development, find new and creative ways to increase quality affordable housing,” she said.

Paul Bolon, Republican candidate for Providence district supervisor. (Bolon campaign)

Dalia Palchik, Democratic candidate for Providence district supervisor. (Jessica Wallach/ Greater Depth Media)

Bolon, 69, said he also wants more schools and argues that county inefficiency has led to higher property taxes that are pushing out middle-income residents. “We’re beginning to look like San Francisco,” he said. “Our middle-class has hollowed out.”

There are no challengers to the Democratic nominees in the other two districts with open seats: Rodney Lusk, marketing director for the county’s economic development authority, in McKay’s Lee district; and former planning commissioner Walter Alcorn in the Hunter Mill district, where Supervisor Catherine M. Hudgins (D) is retiring.

But Herrity is not the only incumbent facing a challenger.

In the Sully District, Supervisor Kathy L. Smith (D) is seeking a second term against Republican Srilekha R. Palle, a manager at the Inova Health Care system hospital network.

Srilekha Palle, Republican candidate for Sully district supervisor. (Palle campaign)

Sully Supervisor Kathy L. Smith (D) (Evan Cantwell)

Palle, 41, wants to reduce administrative burdens on teachers and raise their wages. She also wants to improve traffic safety by introducing more speed bumps and traffic lights in densely populated communities.

Smith, 64, a former school board member, said she wants to make more academic and vocational programs available in Sully schools and plans to push for diversifying the county’s affordable housing stock.

In the deep-blue Mason District, Supervisor Penelope A. Gross is seeking a seventh term against Republican Gary N. Aiken, a chief risk officer at the American Armed Forces Mutual Aid Association.

Supervisor Penelope A. Gross (D-Mason) at a community meeting in 2017. (John McDonnell/The Washington Post)

Gary N. Aiken, Republican candidate for Mason district supervisor in Fairfax County. (Scott Affens)

Gross, 75, pledges to continue trying to upgrade older commercial areas in her district and build more housing. Aiken, 39, said he wants to clean up blighted areas and improve public safety.

In the Dranesville district, Supervisor John W. Foust (D) is pursuing a fourth term against Republican Ed R. Martin. Foust says he wants to focus on fixing roads, getting new sidewalks and attracting commercial development.

Martin, a well-known conservative radio personality, does not appear to have campaigned yet. But he said in a Twitter message that he plans to “drain the swamp” of unnecessary government spending in Fairfax and attack Foust over a resolution he co-sponsored to allocate $200,000 toward legal defense costs for immigrants who are facing deportation.

Linda Sperling, Democratic candidate for Springfield district supervisor. (Sperling campaign)

Springfield Supervisor Pat Herrity (R) (Evan Cantwell)

Herrity, the Republican who has represented the Springfield district since 2008, appears to be the most vulnerable incumbent.

Marketing executive Linda Sperling, his Democratic opponent, said she wants to add more permanent classrooms, consider increasing density in some areas slated for single-family homes, and increase local access to public transportation.

“If you look at a map of public transportation options in the county, you’ll see a big empty space in the Springfield district,” said Sperling, 42, a member of the county’s transportation advisory commission.

Herrity, 59, disputes that, saying he has spearheaded increased Fairfax Connector bus service at the Rolling Valley park-and-ride stop in Burke and pushed for several road-widening projects that include bike lanes and sidewalks.

The son of a former county board chair, Herrity said he wants to lure more recreation-related businesses to Fairfax and plans to continue to work to bring down county pension costs. As potentially the sole remaining Republican on the 10-member board, he stressed that he could be an important dissenting voice.

“I’ve got a long record of accomplishments,” he said. “And I want to continue to be the voice of fiscal common sense on the board.”

Rebecca Tan contributed to this report.