SAN FRANCISCO (KRON) -- Daniel Lurie is leading incumbent SF Mayor London Breed in the San Francisco mayor's race. Breed is trying to convince voters she deserves a second term in office. Initially, she faced four main challengers, all of whom are Democrats: Daniel Lurie is a nonprofit founder dedicated to anti-poverty campaigns. He is also most notably the heir to the Levi Strauss fortune, to which many of his funds – approximately $6 million – were used for his own first mayoral campaign. Aaron Peskin is the president of the Board of Supervisors and often advertises himself as the most liberal of the four candidates. Asha Safaí is a city supervisor and a former labor organizer. Mark Farrell is a former interim mayor of San Francisco and a current venture capitalist.  As of 10:45 p.m. Tuesday, Farrell has dropped out of the mayoral race, a campaign spokesperson confirmed to KRON4. The news comes about two hours after the polls closed. In the latest poll results Lurie had garnered 28% of the vote to Breed's 25%. There are still around 157,000 ballots to process and count, according to the San Francisco Department of Elections. San Francisco uses a ranked-choice voting system in electing its mayor.