Voters go to the polls in Oakland's mayoral election but results could take weeks

Voters in Oakland, California, are going to the polls on Tuesday to pick a new mayor in an election that could reshape the struggling city. The final results, though, may not be known for several days.

That’s because the election will be decided by ranked choice voting. Under the system, voters rank candidates from most to least preferred. In multiple rounds of tallying, the candidate who receives the fewest votes is eliminated, and their supporters’ votes are carried over to their next preferred pick until there is a winner.