The filing deadline was July 28, 2006, with the primary held September 19, 2006. Cantwell consistently led in polling throughout the race, although political analysts saw her as vulnerable this election cycle due to her extremely narrow win in 2000 and discontent among progressive voters. In November, The National Journal ranked Cantwell's seat as number 13 of the top 20 races to watch based on the likelihood of switching party control, and the third-highest Democratic seat likely to flip. However, in an election marked by discontent over the Republican leadership in D.C., Cantwell easily won by a 17% margin of victory.