Gregory J. Nickels is an American politician who served as the 51st mayor of Seattle, Washington. He took office on January 1, 2002 and was reelected to a second term in 2005. In August 2009, Nickels finished third in the primary election for Seattle mayor, failing to qualify for the November 2009 general election, and losing his bid for a third term as mayor. He left office on January 1, 2010.

The 2009 Seattle mayoral election took place November 3, 2009. Incumbent Seattle mayor Greg Nickels sought reelection but finished third in the August 18, 2009 primary election. The general election was instead between Joe Mallahan and Michael McGinn. McGinn beat Mallahan in the election with 51% of the vote share, becoming Seattle's next mayor.