Chicago voters will cast their ballots on Tuesday for their chosen mayoral candidate. In recent months, the race has grown increasingly acrimonious as Mayor Lori Lightfoot faces the possibility of being the first mayor to lose re-election in four decades. 

In all, nine candidates are vying to be one of the two candidates to move on to the second round of voting in April. The four leading candidates according to polls are Ms. Lightfoot; a former head of Chicago’s public schools, Paul Vallas; Congressman Chuy Garcia; and a liberal Cook County commissioner, Brandon Johnson. 

The most important issue on Chicagoans’ minds is the city’s rising crime rates. According to a WBEZ poll from February 9, nearly two-thirds of voters want a mayor who can increase the number of police officers on the streets and crack down on violent criminals. Forty-four percent of voters say “crime and public safety” is their top concern. 

According to a Chicago Police Department report, the total number of crime complaints increased by 43 percent in the last year. Criminal sexual assault and aggravated assault both increased by more than 15 percent, burglary by 20 percent, theft by 54 percent, and motor vehicle theft by 114 percent. 

Ms. Lightfoot was elected nearly four years ago as a crusading police reformer. While serving as the city’s chief law enforcement watchdog under Mayor Rahm Emmanuel, Ms. Lightfoot aggressively pursued police abuse and rapidly increased the number of suspensions and firings. She won the 2019 mayoral election with more than 70 percent of the vote. 

Despite promises of police accountability and reform, Ms. Lightfoot’s tenure has seen a significant decrease in the number of working officers and low morale for those still serving. Since her election, the Chicago Police Department has lost more than 10 percent of its officers. 

Mr. Vallas, who also led the Philadelphia public school system, has embraced a tough-on-crime approach to the campaign. He has criticized Illinois’ abolition of cash bail for violent offenders, which he says has allowed those charged with assault, burglary, and even murder to walk the streets as they await trial. 

“I support ‘no cash bail’ with the following distinction: We have to distinguish between violent offenders and nonviolent offenders,” Mr. Vallas said at a February 14 debate. “Fifteen percent of the murders and the shootings were caused by people out on pretrial release” due to cashless bail, he said. 

Mr. Lightfoot has tried to paint Mr. Vallas as a “Republican in disguise.” Her argument was bolstered by a recently unearthed video from 2009 showing Mr. Vallas describing himself as “more of a Republican than a Democrat.” In January, he was endorsed by the city’s Fraternal Order of Police — one of the largest and most influential unions in Chicago. The union leadership has close ties to President Trump, and hosted a reception with Governor DeSantis on Monday. 

Messrs. Johnson and Garcia are virtually tied in the polls, with both men running to the left of Ms. Lightfoot with the backing of powerful Chicago unions. Mr. Johnson, a former union organizer, has the backing of the Chicago Teachers Union, which went on strike over contract negotiations with Ms. Lightfoot. 

Mr. Garcia ran for mayor in 2015 as a left-wing alternative to Mr. Emmanuel. The congressman moved to Chicago from Mexico at the age of 9 and is calling for both more police oversight and more beat cops walking in certain dangerous neighborhoods. 

A poll released by Victory Research shows Mr. Vallas leading the field with 22 percent of the vote, followed by Ms. Lightfoot at 17 percent. Messrs. Johnson and Garcia each garnered 15 percent. 

The head of Victory Research, Rod McCulloch, told the Sun that the police union endorsement helped boost Mr. Vallas in recent weeks. “There’s no question where his support comes from,” Mr. McCulloch said. “It comes from the northwest part of the city and the southwest part of the city where a lot of first responders live.”

Despite Mr. Vallas’s lead in the first round polls, Mr. McCulloch predicted a competitive race between the Tuesday vote and the April election. “I think he starts off ahead of all of them,” Mr. McCulloch said, referring to Mr. Vallas. “It depends whether or not they can make the ‘Paul Vallas is a Republican’ thing stick.”

At a rally on the South Side last week, the mayor came under fire for what her opponents said was insensitive language. Ms. Lightfoot told the crowd that “any vote coming from the South Side for somebody not named Lightfoot is a vote for Chuy Garcia or Paul Vallas.” 

The implication was that no one in the predominantly Black South Side neighborhood should vote for a Black candidate — like Mr. Johnson — other than Ms. Lightfoot, as that would risk putting either a white man or a Hispanic man in the mayor’s office. Ms. Lightfoot’s campaign had to backtrack, telling the Chicago Tribune that she wants “every Chicagoan to vote,” not just the Black voters on the South Side. 

The first round of the mayoral election will be held on Tuesday. Should no candidate receive a majority of the vote, the top two vote-getters will advance to a runoff in April. 

Were Ms. Lightfoot to fall flat on Tuesday, she would be the first sitting mayor to not move on to the second round since the system was adopted in 1999. She would be the first mayor to lose re-election since 1983.