Oakland Councilmember Abel Guillen, in perhaps the biggest Election Night upset in the East Bay, conceded the District 2 race to Nikki Fortunato Bas early Wednesday morning.

Following an update of election results giving Fortunato Bas a significant boost, Guillen conceded the race in a tweet posted at 12:26 a.m. Fortunato Bas received 50.09 percent of the vote with 100 percent of precincts reporting. Guillen held 43 percent of the vote.

“The voters have spoken and I respect their decision,” Guillen wrote. “While this is not the outcome that I hoped for, I will continue my work to serve the City I love in a different capacity. I congratulate the Councilmember-elect and wish her and our city the best.”

Nikki Fortunato Bas

The result was the first of two upsets in Oakland Tuesday night. District 6 Councilmember Desley Brooks was handily defeated by Loren Taylor.

We did it!!!” Fortunato Bas tweeted Wednesday afternoon. “I think it’s a mutual congratulations. This is our victory–for our community, for our city, and for our movement. It will take all of us to build an Oakland for All of Us! Thank you, Oakland, and I look forward to being your champion at City Hall!”

For Fortunato Bas, the victory caps a year in which she came from virtual political obscurity to becoming a viable candidate backed by strong fundraising, grassroots organizing and significant help from some of the most powerful labor groups in Oakland.

Article was updated Wednesday afternoon.