On Election Night, the more centrist progressives all racked up large vote margins, potentially signaling a significant change in Seattle politics and city government.

But, as expected, these margins shrunk considerably as later votes were counted.

Despite the narrow margins of victory, the sweep of Harrell, Davison, and Nelson represents a clear mandate for change. In addition, Harrell’s margin was the widest of any contested mayoral election in the past 20 years.

But what explains the late surge of very progressive votes? Age.

The late votes were cast by younger voters, many of whom review The Stranger endorsements before filling out their ballots. King County Elections received the largest batch of votes after November 1st – and that group had the youngest median age.

Overall turnout in Seattle was 54%, but older voters (65 and older) cast their ballots in much higher numbers (almost 75%) than voters 18-24 (about 33%) and 25-34 (42%.)

This turnout differential was critical to Harrell and the other centrists. Despite their much higher turnout, voters 65 and older cast only 8,800 more votes than the 25-34 group (63,000 compared to 54,200.)