Sarah Ravani

Nami Sumida

Oakland Mayor-elect Sheng Thao secured defeated her biggest competitor, Loren Taylor, by just under 700 votes in the final round of ranked-choice voting in a nail-biting race. New data shows the city’s voting patterns mostly divided it into two distinct, contiguous areas: One that voted primarily for Taylor and the other for Thao, with a very small area near the border of San Leandro opting for a third candidate.

Thao secured most of her support from middle income households in downtown, West and North Oakland and some parts of East Oakland, including Fruitvale, according to precinct level data of first-choice votes. Taylor performed better with higher income neighborhoods. He received most of his support from the Oakland hills, a high propensity voter area, and parts of deep East Oakland.

The map below shows which mayoral candidate won the most first-choice votes in every Oakland precinct, and clearly shows the geographic divide in the city. Data on who won the final ranked-choice votes by precinct is not yet available.

Thao won despite receiving fewer first-choice votes than Taylor. In total, Taylor secured 41,510, or 33.1%, of first-choice votes and Thao won 39,909, or 31.8% of voted.

But after applying ranked-choice voting, Thao received 57,206 votes, or 50.3% to Taylor’s 56,529 votes, or 49.7%.

Oakland uses ranked-choice voting, which means if a candidate receives a majority of first-choice votes, that candidate wins. If not, the last-place candidate in a given round is eliminated, and voters who selected that candidate have their votes counted for their next choice — a cycle that repeats until a candidate gets a majority. Voters in Oakland were able to rank up to five candidates.

The results of the race have spurred debate about how residents voted, where candidates secured support and whether the close race shows that Oakland voters are divided. And while the data shows a geographic divide, some political experts point to data showing many residents ranked both candidates on their ballots, proving that the divide isn’t as stark as the geographic data suggests.

“It’s probably a homeowner and renters split,” said Jim Ross, a political consultant in Oakland, said of how residents picked their first-choice candidate. “The city of Oakland has always had different neighborhoods with different issues and concerns, but I don’t necessarily think that you see a real city divided.”

“There were a lot of voters who voted for both Loren and Sheng,” Ross said. “There were a lot of people who liked them both and ranked them differently.”

Ross didn’t work on either mayoral campaign, but he supported Thao.

The most surprising aspect of the first-choice vote data is that while Thao secured pockets of support in her council district, which includes the Oakland Hills, she failed to get support from a majority of the district, Ross said. That support went to Taylor and that’s likely due to his endorsement from outgoing Mayor Libby Schaaf, who used to represent that district as a council member and currently lives there, Ross said.

Noah Finneburgh, a political strategist that worked on Thao’s campaign, said the campaign’s strategy included sending volunteers out to neighborhoods where they thought Thao’s message and endorsements would resonate most.

Finneburgh said Thao’s support from middle income households is likely due to her background.

“It’s that she came from poverty and really struggled and has gone through what a lot of folks are going through and she experienced homelessness, she experienced housing insecurity, she’s a renter,” Finneburgh said. “I think a lot of folks can relate to that.”

In addition, Ross said labor organizations rallied behind Thao, which likely resonated with working class families. Thao also pitched herself a consensus builder that brought labor groups, businesses and council members together to broker a deal so that only one business tax would be placed on the ballot, which voters ultimately supported. That was a tangible win she could point to when speaking with voters. Ross said Taylor lacked such a key win to campaign on.

In addition, residents tend to vote ideologically, Ross said. Thao is a progressive and Taylor is a moderate. Allyssa Victory, a progressive grassroots candidate, came in fourth place and most of her votes went to Thao — a clear sign of how residents ranked candidates ideologically on their ballot, Ross added.

While Taylor performed well in some parts of East Oakland, a portion of which he represents as a council member, his overall numbers were still lower due to two other competitors: Treva Reid, who he announced an alliance with, and Ignacio De La Fuente.

De La Fuente, who Ross said cost Taylor the election, secured a lot of support in precincts near the border of San Leandro, which have been heavily impacted by crime. De La Fuente’s tough-on-crime rhetoric resonated with those voters, but Taylor was unable to entice those same voters despite campaigning for more cops. Many of those voters only put De La Fuente on their ballot without ranking anyone as their second-choice, Ross said.

Despite the outcome of a race that saw a progressive and moderate battling it out, some political experts said it’s likely most residents supported both the candidates.

Sean Dugar is one of those voters. Dugar, the executive director of California Ranked Choice Voting Coalition, which advocates for ranked-choice voting, said he ranked both Thao and Taylor on his ballot, but neither as his first choice. Dugar ranked Greg Hodge, a former member of the Oakland Unified School District Board of Education, as his first place choice.

Dugar said FairVote, a similar organization that he works with, released an analysis that showed 22% of voters who chose Thao as their first place candidate on their ballots selected Taylor as their second place candidate. The analysis also showed that 24% of voters who chose Taylor as their first choice on their ballots also chose Thao as their second place candidate.

The analysis also showed that 44% of voters who selected Taylor as their first-place candidate ranked Thao somewhere on their ballot, and 45% of voters who chose Thao as their first place vote also ranked Taylor somewhere on their ballot.

Sarah Ravani and Nami Sumida are San Francisco Chronicle staff. Email: sravani@sfchronicle.com, nami.sumida@sfchronicle.com Twitter: @SarRavani, @namisumida