CHICAGO (CBS) — Mayor Rahm Emanuel’s decision not to seek a third term in office in 2019 stunned the political world on Tuesday. Here are five fast facts about the mayor’s decision, and what it means for the mayor’s race:

1. Emanuel’s announcement came almost eight years to the day after his predecessor, Richard M. Daley, announced he would not be running for a seventh term, after a record 22 years in office. Unlike when Daley handed off the baton to Emanuel by endorsing him for mayor in 2011, there is no clear frontrunner in 2019, with 11 candidates so far lined up for the job.

2. Emanuel’s announcement also comes one day before jury selection begins in the trial of Chicago Police Officer Jason Van Dyke, who is charged with the murder of Laquan McDonald in 2014. The mayor’s handling of the shooting controversy severely damaged his public approval ratings. The release of dashboard camera video of the shooting one year after McDonald’s death touched off a series of protests, demanding the mayor’s resignation. Protesters accused the mayor of intentionally concealing the video until after the 2015 election. Testimony in Van Dyke’s trial likely would have been damaging to Emanuel’s reputation at a time when the mayoral race will be just starting.

3. As with any transition from one mayor to another, Emanuel’s decision not to run again leaves open the question about what his successor’s priorities will be for addressing violent crime, public schools, jobs, the city’s woefully underfunded pension systems, and more. Perhaps the biggest question will be how Emanuel’s decision not to run again will impact the city’s bid to host Amazon’s second headquarters. Amazon CEO Jeff Bezos is expected to announce the location of the company’s HQ2 by the end of the year.

4. Mayor Emanuel also faced the possibility that he might not have been able to run for a third term, as former Gov. Pat Quinn has filed petitions to get a binding referendum on the Nov. 6 ballot, limiting Chicago mayors to two terms in office. Emanuel allies challenged those petitions, and while it appears term limit supporters gathered enough signatures, the measure could still face another legal challenge. The City Council has placed three non-binding referendums on the ballot, which could block Quinn’s term limits proposal from making it on the ballot.

5. Although 11 candidates already have announced plans to run for mayor in 2019, there is no clear frontrunner, and no City Hall insider in the field, a rarity for mayoral elections in Chicago. Emanuel did not announce plans to endorse any of the candidates running against him. So far, the candidates who have announced they are running include former Chicago Police Supt. Garry McCarthy, former Chicago Police Board President Lori Lightfoot, former Chicago Public Schools CEO Paul Vallas, Cook County Circuit Court Clerk Dorothy Brown, former CPS principal Troy LaRaviere, millionaire businessman Willie Wilson, community activist Ja’mal Green, former aldermanic candidate John Kozlar, tech entrepreneur Neal Sales-Griffin, DePaul student Matthew Roney, onetime mayoral candidate Amara Enyia and radio show host and writer William Kelly.