With only 479 more votes as of Wednesday's tabulation, District 4 supervisor candidate Joel Engardio has defeated incumbent Gordon Mar in an upset— signaling a potential shift in the balance of power on the SF Board of Supervisors.

Mar conceded to Engardio on Wednesday, despite the still slim lead, saying on Twitter, "It’s increasingly unlikely that there are enough votes to change the outcome of our race, and a few minutes ago, I called Joel Engardio to concede and offer my congratulations."

Mar added, "He worked hard on his campaign, and I hope he works just as hard on behalf of District 4."

Engardio, who ran a "law-and-order" themed campaign, becomes the first LGBTQ person to represent a district on San Francisco's westside. A San Francisco Democratic Party Central Committee member and journalist, Engardio supported the recall of three school board members — whose recall was partly motivated by the unpopular move to end merit-based admissions at Lowell High School, which is in District 4.

District 4 encompasses all of the Outer Sunset, as well as the Parkside and Lakeshore neighborhoods, and the area west of Stonestown and south of Sloat Boulevard. This latter section of the city was added to the district as part of redistricting — and redistricting, Mar said in his concession statement, is to blame for his loss.

Engardio had run for supervisor three previous times, but in District 7, which is where his home used to reside prior to redistricting.

"People chose me,” Engardio tells the Chronicle. “It doesn’t make sense to say it was only because of redistricting."

Mar opposed the recall of the three school board members earlier this year as well as the recall of District Attorney Chesa Boudin — and as KRON4 notes, both recalls were "heavily supported" in this part of the city.

As the Chronicle reports, this upset in Mar's defeat is notable as the first time in 20 years that an elected incumbent supervisor has been unseated by a challenger — the only incumbents to face defeat in two decades were mayoral appointees.

Mar was part of the progressive voting bloc on the Board of Supervisors which, in last week's election, has grown smaller. While we don't know how Engardio will vote once he takes office, the prevailing wisdom is that his election shifts power back in the moderate direction of Mayor London Breed, with the progressives' six-vote solid majority dwindled to five (with Aaron Peskin, Connie Chan, Dean Preston, Hillary Ronen, and Shamann Walton often voting together) — though supervisors Rafael Mandelman, Matt Dorsey, and Myrna Melgar sometimes vote with the progressives as they see fit.

This also may mark the first time, come January, that the SF Board of Supervisors has had three openly LGBT members serving at the same time, with Mandelman, Dorsey, and Engardio.

Previously: Meet Joel Engardio: A Supervisor Candidate With A Thing For Owls

Photo via engardio.com