She made history four years ago as the first openly gay, Black woman to win the mayor's office.
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Tuesday night, she made history again, by becoming the first elected incumbent in 40 years to not win a second term, with Paul Vallas and Brandon Johnson advancing to a runoff election.
Mayor Lightfoot had a contentious relationship with the City Council and the unions, but Tuesday night, she told the crowd she was proud of her work in the city.
Safety and crime were the top issues for voters, something the top two candidates pushed during their campaign. Lightfoot was criticized by them for rising crime numbers.
Lori Lightfoot concedes after failing to qualify for runoff election
Lightfoot said this was a tough year for incumbents, but she is holding her head up high.
"Regardless of tonight's outcome, we fought the right fights and we put this city on a better path," Lightfoot said. "Now as we all know in life, in the end, you don't always win every battle. But you never regret taking on the powerful and bringing in the light."
Lightfoot said with her daughter in high school, she does plan on staying in Chicago and she will be rooting for the next mayor of the city.