The two candidates competing in the June 12 primary for the Arlington County Board are what voters might expect of a Democrat in the affluent, educated, rapidly urbanizing enclave — highly prepared, willing to get into the details of local issues and claiming fealty to the county’s tradition of careful, long-term planning.

One, Matt de Ferranti, 44, is taking a well-trod path to elective office. He served on multiple civic groups as soon as he moved to the county in 2013, racked up the backing of past and present elected Democrats and raised plenty of money — he reported more than 200 cash donations over $100 in his last financial report.

The other candidate, Chanda Choun, 30, is leaningon his personal story and his enthusiasm for change, which he says reflects the evolving demographics among Arlington voters. He describes himself as a “refugee immigrant” who moved to Arlington in 2015, volunteered in his neighborhood and pledges he will marry, raise a family, die and be buried in Arlington. His campaign has been primarily self-funded.

The winner of the primary will face well-financed incumbent John Vihstadt in the November general election. Vihstadt, a Republican turned independent, won a special election in 2014 and, seven months later, was elected to a full four-year term in the general election. He was the first non-Democrat to win a County Board seat in 15 years.

This election is not a replay of 2014, when voters were upset about high-cost public works projects that an earlier County Board had approved — the now-abandoned Columbia Pike streetcar, a $1 million bus stop and an overbudget Long Bridge aquatics center. Vihstadt’s election, combined with the subsequent departures of three of the remaining board members and the county manager, has altered that dynamic.

De Ferranti says it is time to return Arlington’s government to its progressive roots, and Choun wants the next generation of voters to have another peer on the board. (Chair Katie Cristol (D), 33, is also a millennial.)

In terms of policy, de Ferranti and Choun hew to what progressive voters in Arlington have long supported — government efforts to improve transit, attract new businesses, encourage more affordable housing, strengthen K-12 schools and preserve parks and open space.

Their differences are harder to find.

De Ferranti, legislative director for the National Indian Education Association, says he offers relevant experience on the most important issues facing Arlington — economic opportunity, housing affordability and schools.

While more room for the booming student population is needed, school construction needs to be more cost-effective, he said in an interview. The County Board needs to be “courageous” in addressing school capacity, he said, but the hot topic of whether to build a fourth high school near Arlington’s career center needs more public examination. “We need to find out exactly what we can afford,” he said.

He told other Democrats at a candidates night in May that Vihstadt is “a decent person” and “we need to relate and persuade” his supporters to return to the Democratic fold. But he also criticized several of Vihstadt’s signature votes.

“It’s reasonable to ask that the cost of the [Long Bridge] aquatic center slide down from $90 million to $60 million, but then why are you voting against it?” he asked. “There’s a demonstrated need in that part of the county for a pool. “

Choun (pronounced Choon), a cybersecurity manager with a private technology firm, has also studied up on local issues and can discuss the need for preparing for the future. But he said his campaign is primarily about adding “a new face, a different voice,” to the County Board.

“When it comes to any organization, you get better performance outcomes when you have people of different backgrounds and skill sets,” he said.

He touted his biography — he was brought to the United States from Cambodia as a young child and enlisted in the Army at age 17 — as an important story line for progressive Democrats.

“We at the local level in Arlington can be an antidote to what we see in Washington and in the Trump administration, by electing a refu­gee immigrant,” said Choun, who serves part time in the Army Reserves. “I believe I embody the American Dream.”

Choun urges better marketing of Arlington to attract new businesses and says the county should work to lure defense agencies back to the community. Arlington’s smart-growth policies need to be extended to places such as the Lee Highway corridor and along Columbia Pike, he said, adding that the county needs to start preparing for new individual transportation options such as dockless bikes, scooters and shared roller skates, while also accommodating pedestrians.

He acknowledged the need for new schools, which is usually funded by borrowing, but also noted that Arlington is bumping against its self-imposed debt limit of 10 percent.

“So we need to consider how to get more revenue,” he said. While he would not rule out a tax increase, he said expanding the tax base is a better option.

If he wins the primary, Choun said, it will be with a broad coalition of immigrants, professionals and millennials who will campaign for him through the general election.

“I’m not running to beat [Vihstadt],” Choun said. “I’m running to succeed him.”