Katie Wilson, a community organizer campaigning on higher taxes for the wealthy and expanded social services, is poised to become Seattle’s next mayor after late ballots widened her lead over incumbent Bruce Harrell.

Wilson, 43, a political newcomer, led by 1,976 votes with only a small number of ballots remaining. The Seattle Times projected her as the winner on Wednesday afternoon. Harrell is scheduled to address supporters on Thursday.

The race reversed initial election-day trends. Harrell had led by more than seven percentage points when polls closed on November 4, but Washington’s mail-in ballot system steadily eroded his advantage. Wilson garnered backing from labor unions and progressive activists, while Harrell was supported by major business groups and senior state officials.

Wilson’s victory completes a sweep of progressive wins in key city races, including city attorney and city council president, producing a council more likely to endorse her proposals for levies on corporations and high-income residents.

Seattle faces economic uncertainty as Amazon and Microsoft recently cut jobs and some companies relocate to neighbouring cities. Wilson has signalled caution, proposing levies on vacant properties, a city-level capital gains tax, and a tax on professional services. Housing affordability remains a central campaign focus.