Harrell, who is currently serving his second term on the council, launched his campaign on Tuesday.
"I am running for Mayor because people in Seattle need strong, proactive leadership and a leader who inspires our city to build a pathway to success for all; a leader who will jumpstart our city with fresh ideas and energy," he said in a written statement.
Harrell said he plans to convert existing community centers into "empowerment centers" that serve youth and seniors, and create 20 community service officer positions -- approximately four per precinct -- to "conduct meaningful outreach" and help curb gang violence.
Harrell said he planned to establish a $20 million endowment fund for the "College For Everyone" program, which would allow all graduates of Seattle Public High Schools to attend South Seattle Community College for free. The proposal expands on an existing program that guarantees free tuition at the community college for graduates of two Seattle schools.
Harrell is the last to join an already-crowded race. Also in the running are incumbent Mike McGinn, Seattle City Council member Tim Burgess, former Seattle City Council member Peter Steinbrueck, and state Sen. Ed Murray.
Burgess, who is also serving his second term on the council, has not always agreed with McGinn; they were on opposing sides of the Alaskan Way Viaduct and tunnel project. Burgess also wants street car expansion and transportation improvements.
Steinbrueck said he'll concentrate his efforts on schools, transportation and sustainable growth. Something he hopes not to see in the future is an NBA and hockey arena in the SoDo area.
McGinn, a former Sierra Club leader, said he would emphasize education, transportation and neighborhood safety in the upcoming campaign.
Murray has established an exploratory committee to build the foundation for a campaign. Because of rules for state lawmakers, Murray is unable to raise money until the Legislature completes its session.