RELATED: Bay Area election results
On Thursday, Leno was 255 votes ahead of Breed. On Wednesday, Leno was 1,100 votes ahead.
The update shows Mark Leno with 50.04 percent of the vote and London Breed is at 49.96 percent.
She led on election night but Leno took over the lead after ranked-choice voters were counted.
Leno has picked up thousands of second-place votes from Jane Kim supporters.
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