CHICAGO — There are decades of entrenched Chicago political tradition, and then there is the stunner of a mayoral election in the city Tuesday. The ballot was the most crowded in history, with 14 candidates. The top two finishers, Lori Lightfoot and Toni Preckwinkle, are both African-American women, guaranteeing that Chicago will have a black woman as mayor for the first time.

Early Wednesday, Lightfoot and Preckwinkle were out on Chicago streets greeting voters, setting off on a frenetic, five-week head-to-head campaign until the runoff in April.

Here are three things that happened Tuesday that showed just how much Chicago’s political ecosystem has transformed.

A Daley lost

There are some names in Chicago politics that are practically synonymous with wide support, major financial backing and a ride to victory. Daley might be the biggest.

In the crowd that came out to support William M. Daley, 70, at an election party Tuesday night, there was little doubt that Daley, a member of a political dynasty, would be among the top two finishers. The promise of a third Daley mayor seemed near.

It was a cheery scene filled with members of Chicago’s elite: bankers, real estate moguls, lawyers, philanthropists. Asked why they voted for Daley, who is known as Bill, the reasons tended to echo. They trusted his business acumen, his experience, his loyalty to the city.

And, of course, because he was a Daley.

“I worked with Richie,” said Dorian Jones, a consultant, referring to former Mayor Richard M. Daley, Bill’s brother, Chicago’s longest-serving mayor.

“It’s a family business,” said Carmen Caldero, who worked in the 1970s with former Mayor Richard J. Daley, the father of Richard M. and Bill. (Richard J. Daley, the city’s second-longest serving mayor, was elected in 1955 and served until he died in office in 1976, and Richard M. Daley, was mayor from 1989 to 2011.)

By the end of the night, Daley stunned the crowd by the making a concession speech, thanking his wife, Bernadette; his family and staff; and his supporters, most notably, Ken Griffin, the richest man in Illinois.

In the end, the Daley name cut both ways. He won 15 percent of the vote, not enough to qualify for a runoff. Many voters said as they headed to the polls that they had sour memories of previous Daleys, didn’t believe in some of the choices they had made and were tired of the hold that the family had on municipal politics.

It wasn’t about race

Chicago, a deeply segregated city, has a population roughly divided among African-Americans, Latinos and whites. And over time, candidates in Chicago have counted on a sizable number of voters from their own race or ethnic group.

But this election was different, as a ward-by-ward map of election results revealed. Both Lightfoot and Preckwinkle appealed to mostly white communities beyond predominantly African-American neighborhoods on the South and West sides.

Lightfoot’s base was on the North Side, a historically white part of the city where she had leads in 10 City Council wards, including a large margin in the ward near Lake Michigan that includes Wrigley Field.

Preckwinkle’s base was along the South Side lakefront, where more black people live. But she came in second to Lightfoot in eight North Side wards, outpolling Daley and several other white candidates.

Both candidates struggled in some mostly Hispanic neighborhoods, where voters tended to favor Latino candidates, and in traditionally white enclaves on the Northwest and Southwest sides.

Now the scramble begins to compete for voters who supported the other candidates, particularly those who voted for Daley, mostly downtown and on the more conservative Northwest Side; and for Willie Wilson, the fourth-place finisher, who won in heavily African-American wards on the South and West sides.

Progressivism might have changed

Preckwinkle, 71, has spent most of her career immersed in Chicago government, climbing from 4th Ward alderman to Cook County Board of Commissioners president and chairwoman of the county Democratic Party. Along the way, she has built a reputation as a true progressive and a co-founder of the Progressive Caucus on the City Council. She has favored criminal justice reform, affordable housing, repairing relationships between police and communities, and economic development in neglected neighborhoods in Chicago.

On Tuesday, she was narrowly surpassed in votes by Lightfoot, 56, who has never held elected office and has promised “a new progressive vision for the city.”

In the five weeks leading up to the runoff in April, both Lightfoot and Preckwinkle are expected to battle over the meaning of the term “progressive” in a heavily Democratic city.

Lightfoot, a former federal prosecutor and former president of the Chicago Police Board, an oversight group, is not far apart ideologically from Preckwinkle on many of the issues facing the city.

But she is trying to define herself as the true progressive in the race partly by highlighting Preckwinkle’s time in government, especially her relationship with Ed Burke, a Chicago alderman who has been charged with attempted extortion and held a fundraiser for Preckwinkle. She returned the money and stripped Burke of his role as chairman of a county committee. (In things that haven’t changed when it comes to Chicago elections, Burke was re-elected Tuesday despite facing a criminal charge.)

Preckwinkle has indicated that she will fight to hold onto the label.

“I’m the most progressive candidate in this race, and I’ve taken my progressive values to whatever job I’ve taken on,” she said in a debate last month.

On Tuesday night, she reflected on Chicago’s shifting political order.

“I remember when ‘progressive’ wasn’t a positive,” she said. “It was at best a euphemism for ‘unelectable.’ Those of us who proudly claimed it had to fight to transform the political landscape.”

This article originally appeared in The New York Times.