Montgomery County council member Marc Elrich (D-At Large), who is running for county executive, picked up an endorsement from the local Sierra Club. (Sarah L. Voisin/The Washington Post)

The Montgomery County Sierra Club has shifted its endorsement to Democratic county executive candidate Marc Elrich, after the environmental club’s first pick, Roger Berliner, lost to Elrich in the June primary.

The nod from the group, which has 6,000 members in the county, adds to the wide array of endorsements from labor unions and progressive groups that Elrich had received in the days leading up to the primary election.

The environmental group had endorsed council member Berliner (D-Potomac-Bethesda) for the liberal county’s top elected position, but Berliner placed fourth in the six-way race. Elrich, a 12-year at-large council member, won the Democratic nomination by just 77 votes over Potomac businessman David Blair.

Elrich will face Republican Robin Ficker in the November general election — and, potentially, longtime council member Nancy Floreen, a former Democrat who changed her party to unaffiliated and announced plans to run as an independent.

The Montgomery County Board of Elections planned to announce Wednesday morning whether Floreen has submitted enough valid signatures to qualify for the ballot, board president Jim Shalleck said.

Dave Sears, chair of the Montgomery County group of the Sierra Club, said the group’s endorsement decision was made over the weekend.

He lauded Elrich for his leadership on environmental issues, including on developing a bus rapid-transit system for the county. Elrich has received the club’s endorsement before, during his council runs.

“Marc is the number-one proponent for the BRT system, and the Sierra Club is very much in favor of transportation investments that will enable people to get around from place to place without using their cars,” Sears said.

Elrich said he was “really happy” about the endorsement, calling the nod “a good validator” among voters.

“It’s a lot of voters. And it’s a lot of people who are concerned about the environment,” he said.

Sears said that the Sierra Club had interviewed Ficker and also sent an endorsement questionnaire to Floreen but that she did not return it by the group’s deadline.

Floreen said her office had told the group she would return the questionnaire once she officially qualified as a candidate.

The Sierra Club also added endorsements for Andrew Friedson, the Democratic candidate for council District 1; Gabe Albornoz, who won the Democratic nomination for one of the four at-large council seats; and District 3 council member Sidney Katz (D-Gaithersburg), Sears said. The club previously had endorsed Katz’s opponent, Ben Shnider. It has not yet made an endorsement for the upcounty District 2 council seat.