McGinn, who was mayor from 2010-2014, is challenging incumbent Ed Murray, who defeated him in 2013. Murray, who led the push to increase Seattle’s minimum wage to $15 an hour and has emerged as a critic of President Donald Trump’s policies, was not expected to face serious competition for re-election.
However earlier this month a man sued Murray, saying 30 years ago he sexually abused him when he was a teen. Murray has forcefully denied the allegations.
McGinn did not directly address the lawsuit at a news conference announcing his candidacy. He said he had been considering a run for some time and wanted to have a "conversation about the future" as rents and housing prices soar amid growth by tech companies like Amazon.
"We can't let this city become a San Francisco," McGinn said. "It's harder and harder to be able to afford to live here."
McGinn said he'd push for a city income tax on the wealthy, knowing it would lead to a court challenge. In 1984, the state Legislature approved a law that prohibits a county, city or city-county from levying a tax on net income. McGinn also said he'd look for cuts in the city budget and criticized Murray and the City Council for pushing "deeply regressive" sales and property tax to address problems like homelessness.
McGinn, a former Sierra Club activist and attorney, was an often a combative presence at City Hall who thrilled some but often annoyed Seattle's power structure.
Known for sometimes riding his bicycle to campaign and city events, McGinn pushed for more public transportation options and opposed a $3.1 billion project to replace an elevated state highway along Seattle's waterfront with a tunnel his predecessor and the Legislature approved. McGinn pushed a 2011 citywide referendum on the tunnel project. Voters ended up supporting the tunnel, dealing McGinn a significant political blow, though the tunnel boring machine later broke down, causing significant cost overruns. The tunnel is now scheduled to open in 2019, three years behind schedule.
McGinn also vetoed a measure passed by the City Council that would've allowed police to cite aggressive beggars. The city's downtown businesses supported the panhandler ordinance, saying people felt unsafe. McGinn said the idea unfairly scapegoated homeless people.
He was criticized in 2012 for fighting federal officials who sought greater oversight of the city's police force. Ultimately, Seattle agreed to an independent monitor of the city's police department following a report that found officers routinely used excessive force.
In a statement, Murray's campaign said he has successfully built coalitions to raise the minimum wage and pay for more affordable housing. The campaign said McGinn was "divisive and confrontational" as mayor.
"We believe that the people of Seattle do not want to return to those bad old days," the statement said.
At his news conference, McGinn said: "I've had time to reflect on my time in office. I've mellowed."