Freshman delegates Mark Keam (D-Fairfax), Luke Torian (D-Prince William), Kay Kory (D-Fairfax) and Robin Abbott (D-Newport News) take the oath of office in 2010. Keam was the first Korean American elected to the Virginia General Assembly. (TRACY A WOODWARD/WASHINGTON POST)

The roster of candidates running for office in Fairfax County this year is at odds with the demographic changes sweeping through the area, despite a push for more diversity from ethnic groups and some party leaders.

Forty-two percent of the county’s 1.1 million residents are either Asian, Latino or African American — up from a third of the county’s population in 2000. During the same period, the number of foreign-born residents grew from about one-fifth of the population to nearly a third.

But nearly all the candidates for office who filed their paperwork by Thursday’s deadline are white, and most are male.

Virginia Republican Party Chairman John Whitbeck illustrated a desire for diversity when he issued “a statement of support” for the only Latino running for the Board of Supervisors — John Guevara, in the Sully District.

There are no Asians or African Americans vying for seats on the board, which includes one person of color, Catherine M. Hudgins (D-Hunter Mill), who is African American.

“When I see candidates that I feel like are the future of the Republican Party, I have to recognize them,” Whitbeck said in an interview.

In response to complaints from supporters of other Sully candidates who said the party chairman should not have weighed in so early, Whitbeck said he is not officially endorsing Guevara but rather is trying to promote diversity.

“I do think the Republican Party is not doing minority engagement to the fullest extent possible if it’s not eventually nominating candidates that don’t look like me, a white male,” Whitbeck said. “We really need to have an open enough party where we’re nominating people from all communities.”

Another Republican, Korean American Sang Yi, is running to unseat state Del. David L. Bulova (D-Fairfax) in the House of Delegates.

Democrats are fielding two Hispanic candidates for school board, Dalia Palchik in the Providence District and Karen Keys-Gamarra in Sully. A third Latina, Democrat Joana Garcia, will challenge state Del. David B. Albo (R-Fairfax) in the House’s 42nd District.

But, even though Democrats have more diversity among officials already in office, party leaders echoed Whitbeck’s frustration at finding people of color who are willing to run.

“It’s a tough job, recruiting candidates,” said Sue Langley, chairwoman of Fairfax County’s Democratic Party Committee. “We can always do better.”

Should he win in Fairfax’s Sully District, Guevara — a Mexican American originally from Glendale, Calif. — would be the first Latino ever elected supervisor in the county.

No Asians have been elected to the board, either, though Ilyrong Moon, a Democrat who has served as the county school board chair, came close in 2009 — losing by 89 votes in a special election to Republican John Cook, who still holds the Braddock District seat.

“I see myself as part of the next generation” of leadership in the county, said Guevara, a conservative who heads a homeowners association and will face off in an April 25 firehouse canvass primary against two other Republicans, former county electoral board secretary Brian Schoeneman and Planning Commissioner John L. Litzenberger Jr.

School board member Kathy Smith (Sully) is the Democratic nominee in the contest, which will determine the successor to longtime supervisor Michael R. Frey (R).

The race is one of two open seats for supervisor in Fairfax County this year. The other is in the Mount Vernon District, where Supervisor Gerald W. Hyland (D) plans to retire.

None of the candidates in that race or in the Mason District — where Supervisor Penelope A. Gross (D-Mason) faces a primary challenge — are people of color.

Community activists argue that diversity among candidates and elected officials isn’t just about political empowerment. Candidates from different cultural backgrounds, they say, offer a broader range of perspectives on issues such as schools, transportation and health care.

For instance, “Hepatitis B and C are huge risk factors in Asian communities, and we don’t do anything special in terms of screening for schools,” said Grace Han Wolf, a Herndon Town Council member who is among a group of Korean American officials trying to recruit more candidates. “We’re missing out on a significant amount of voices that have concerns the mainstream is not aware of.”

Many Asians and Latinos in Fairfax County are not part of the local party machinery, said Cesar del Aguila, a former chairman of the county Democratic Party committee who has pushed for more Latino involvement. That means they’re unlikely choices for nomination, or to get much support if they run.

“The farm team of candidates tends to come from the group in there now,” Aguila said. “People within the party tend to like the people they know.”

In addition, for many immigrants, political involvement is a secondary concern, said Ting-yi Oei, president of the Coalition of Asian Pacific Americans of Virginia, which hosts candidate forums for Asian Americans in hopes of cultivating more engagement.

“Their interest is really in succeeding, meaning getting their families settled and finding good jobs,” Oei said.

Del. Mark L. Keam (D-Fairfax), who in 2009 became the first Korean American elected to Virginia’s General Assembly, said the political tide is slowly turning. He has been suggesting names of Asians and Latinos for local commissions and boards, and he said other elected officials support that effort as a way to groom potential candidates.

“You need a base to start running for office, and getting your name out there,” Keam said. “I tell people to have a 10-, 20-, 30-year plan.”

On the other hand, he added, “If we always wait our turn, there will always be lots and lots of people in front of us.”