Erik Gutshall, who is running in the June Democratic primary for Arlington County Board. (Alex Orosco/Gutshall campaign)

The lone Arlington County Board race this spring is shaping up as a referendum on two years of political upheaval in the liberal Washington suburb, with incumbent Libby Garvey defending her efforts to steer the board in a more moderate direction and challenger Erik Gutshall slamming her for abandoning the county’s liberal traditions.

In their second debate Wednesday night, the two Democrats sparred over the board’s transparency, its lack of progress on improving transit on Columbia Pike, and policies involving affordable housing, with Gutshall saying that Garvey had betrayed the party faithful by embracing overheated rhetoric and creating “political wedge issues” even when there is consensus.

“We must make long-term strategic investments and reject the false choice that fiscal responsibility somehow demands we shortchange our future,” said Gutshall, who announced hours before the debate that he had been endorsed by 16 current and former local lawmakers, ranging from legislators to board members.

Garvey, a board member since 2012 who assumed the rotating chairmanship in January, countered that she has made meetings more transparent, improved board members’ working relationships and has pushed through the appointment of an ombudsman and an internal auditor.

Libby Garvey is chairman of the Arlington County Board (Nadya Lutz)

Citing a continued need for change in the county, she tried to turn Gutshall’s list of endorsements into a weakness rather than a strength.

“If you want to look at who’s moving forward, you might want to look at the endorsements each of us have,” Garvey said, adding later: “Most of the people who were on the [County] Board before we made changes are supporting my opponent.”

The June 14 Democratic primary, whose winner will almost certainly win the seat in November’s general election, is shaping up as a struggle over whether Arlington residents will support the moderate-to-conservative coalition formed in the last two years by Garvey and board member John Vihstadt, a Republican-turned-independent; or instead will endorse the more liberal policies represented by the traditional Democratic establishment.

Garvey narrowly won a low-turnout special election in spring 2012 to fill the seat vacated by Barbara Favola (D), who had become a state senator. Garvey then won the higher-turnout general election later that year with 58 percent of the vote.

But she quickly alienated her colleagues on the board by opposing the Columbia Pike streetcar project. The next year, she angered local party stalwarts by supporting Vihstadt over the Democratic nominee in another special election. She was forced to temporarily resign from the local party’s leadership committee in 2014.

Vihstadt and Garvey have allied themselves on a series of fiscally conservative votes, which culminated in the cancellation of the long-planned streetcar project.

Gutshall is trying to capitalize on what remains of that anger to unseat her. A first-time political candidate who serves as vice-chair of the local planning commission, he has out-raised her (although she has a bigger cash balance from earlier fundraising), and won the first non-scientific straw poll of the election season.

At the debate Wednesday, he attacked what he called Garvey’s lack of leadership and said that despite her support of openness, she engineered the creation of a new “strategic priorities blue-ribbon panel” last month without public notice or input, which “pushed aside” the work of hundreds of local residents on a similar Community Facilities Study that came out last fall.

Garvey said her leadership is evident from her 15 years on the Arlington School Board. And she took credit for starting to erase years of animosity between the county and the Republican-majority General Assembly.

“I’m pleased to say that over the past couple of years, relations with Richmond for this County Board have improved quite a bit,” Garvey said. “Part of it helps having John Vihstadt on the board . . . . I will tell you, I have been meeting with the Republican leadership, too. I won’t say who it is because it puts them in an uncomfortable position and me in an uncomfortable position, but we work together to get transportation [improvements] done.”

The next debate is set for the monthly breakfast of the Arlington Democrats, Saturday at 8:30 a.m. at Busboys and Poets in Arlington.