Lori Lightfoot won a resounding victory Tuesday night to become both the first African-American woman and openly gay person elected mayor of Chicago, dealing a stinging defeat to a political establishment that has reigned over City Hall for decades.

After waging a campaign focused on upending the vaunted Chicago political machine, Lightfoot dismantled one of its major cogs by dispatching Cook County Board President Toni Preckwinkle, whose candidacy had been hobbled in part by an anti-incumbent mood among voters and an ongoing federal corruption investigation at City Hall.

Lightfoot’s campaign, which started last May as a long-shot bid to replace the city’s clouted politics with inclusive change, took the former federal prosecutor and first-time candidate from toiling in relative political obscurity to toppling the head of the Cook County Democratic Party.

“Today, you did more than make history,” Lightfoot told hundreds of supporters at the Hilton Chicago on Tuesday night. “You created a movement for change.”