Four years ago, billionaire businessman Michael Sacks wrote a $200,000 check to Brandon Johnson’s inaugural committee and went to see the mayor-elect two days after his runoff victory to advise him on how to set up his administration.When Johnson launched his campaign for a second term last month, he named one man as his primary political opponent: Michael Sacks.How did their once promising relationship deteriorate? And who is this Chicago power player now in the eye of the political storm in the mayoral election — and in the elected school board races that will serve as Act 1?It depends on whom you ask.“Michael has obviously been incredibly successful in business. But he also understands that success isn't just about getting your clients a return on their investment,” said former President Barack Obama in a video naming Sacks as Crain’s Man of Year in 2025.“It's about strengthening your community, looking out for your city, creating opportunities, and leaving the world a little bit fairer and a little bit better than you found it.”Jackson Potter, vice president of the Chicago Teachers Union, takes a far different view. He says Sacks wears the jacket for the role he played as “primary bundler” for former Mayor Rahm Emanuel.“He supported the mayor, or stood by silently at best, while he closed the greatest number of schools in American history in 2013, almost exclusively in the Black community,” Potter says. “It's Project 2025, Chicago-style. That dismantling of public education certainly has his fingerprints all over it. The cover-up of police murders, the closing of mental health clinics. That’s his legacy.”Sacks, 64, has long been a fixture in political circles and is a major Democratic donor.He helped recruit JB Pritzker to run for governor. He was Emanuel’s point person on economic development, finance and education funding issues — and the architect of the Neighborhood Opportunity Fund that shared the wealth of Downtown development with long neglected South Side and West Side neighborhoods. He also was the chief fundraiser for the Democratic National Convention that Chicago hosted in 2024. Mayor-elect Brandon Johnson speaks about the Democratic National Convention being held in Chicago in 2024 during a news conference at the Shedd Aquarium in April 2023. Michael Sacks is behind Johnson, on the left.Anthony Vazquez/Sun-Times But all of those roles were, for the most part, behind the scenes.That changed when Sacks started putting his fortune behind Common Ground Collective, a newly formed political action committee that has targeted Johnson’s City Council allies, run commercials opposing provisions of the mayor’s 2026 budget proposal, and is now supporting anti-CTU school board candidates in the upcoming election Nov. 3.A Council majority ultimately rejected Johnson’s corporate head tax in 2025, and Johnson blamed Sacks for the defeat, a claim Sacks has denied.The two had already clashed over the wording of a 2024 resolution calling for a ceasefire in Gaza that passed the Council after Johnson cast the tie-breaking vote.Johnson declined an interview for this story. But he has implied publicly that he believes his ceasefire vote sparked some of the political opposition he faces today."I spoke out against how the Palestinians were being treated... the genocide that has taken place. It takes a great deal of courage to take these positions, and I know firsthand, because I experienced political retribution as a result of my position,” Johnson said at a news conference over the summer.Sacks would not agree to an on-the-record interview for this story, but instead chose to provide selective responses to questions from the Chicago Sun-Times and WBEZ.Sacks’ beginnings Sacks grew up in a 1,250-square-foot, three-bedroom house in Lincolnwood. His father had a small family insurance brokerage — until the Blizzard of '67 changed everything.During the record snowstorm that buried Chicago, Lee Sacks was walking to a neighborhood drugstore to get food and medicine for his son, Michael, who had chickenpox. He had a chance meeting with a neighbor from down the street, Judd Malkin.They forged a friendship that ultimately led Malkin to invite Lee Sacks to provide the insurance for his new company, JMB Realty.“Judd said, ‘We’ve got this new real estate company, why don’t you fold your business into our company? We’re going to need insurance,’” Michael Sacks told the Sun-Times for his father’s obituary. “It turned out to be wildly successful.”With his good fortune, Lee Sacks taught his children to give back and live by the Hebrew phrase “Tikkun Olam,” which means “repairing the world,” Sacks said.“He is driven very much by the values of helping those less fortunate. To those who are given much, much is expected. Michael lives by that ethos. That’s what I love about him,” Emanuel told the Sun-Times.Sacks graduated from Niles West High School, got an undergraduate degree from Tulane and a law degree and an MBA from Northwestern.In 1990, he took a job with Grosvenor, a small asset management firm in Chicago with six employees and several hundred million dollars in assets.One of the investments in Grosvenor’s portfolio was with now infamous financier and con artist Bernie Madoff. Sacks started digging into the returns and declared them too good to be true. After an in-person meeting with Madoff in New York, Sacks says he was “very uncomfortable and had the firm redeem all capital.” Financier and con artist Bernard Madoff, shown arriving at Manhattan federal court in 2009 in New York City, drew suspicion from Michael Sacks before Madoff’s downfall. Stephen Chernin/Getty Images “It wasn’t hard to see” the fraud, Sacks told the Sun-Times. “I was wrong for 17 years before I was very right.”By the age of 30, Sacks had already made his first million dollars. Within four years, he was the firm’s CEO.Under Sacks’ 32-year leadership, Grosvenor has grown from a boutique firm in a relatively new industry to a corporation managing $91 billion in assets for a global client base with offices in New York, Los Angeles, Toronto, London, Frankfurt, Tokyo, Hong Kong and Seoul.Sacks owns a home on one of the wealthiest blocks in Chicago and has residences in Highland Park, Colorado and Florida. He travels extensively for business on a Grosvenor-owned corporate jet and reimburses the company for any private travel.Causes Sacks bankrollsSacks has used his wealth to bankroll an array of causes, including gun violence prevention, women’s reproductive health and public school scholarship programs. He created the Sacks Family Scholarship fund, which has provided 162 CPS students with no-loan scholarships to attend Northwestern, where he sits on the university’s board of trustees.Sacks is also a founding member of the Obama Foundation, and helped save the Sun-Times at a time when the Chicago Tribune was eyeing a purchase of the newspaper.Sacks and his wife, Cari Sacks, have used their fortune to influence local politics. Since the beginning of last year, the couple has spent $9.2 million on Illinois-specific Democratic candidates or causes, according to campaign records.Sacks did not get involved in the 2023 mayoral race. But this election cycle he has given about $500,000 to mayoral challenger Secretary of State Alexi Giannoulias. Secretary of State Alexi Giannoulias announces his run for Chicago mayor at an event in Bronzeville Aug. 2. Candace Dane Chambers/Sun-Times More controversially, Sacks has made off-and-on contributions to the American Israel Public Affairs Committee, the political arm of the American lobby for Israel in Washington, D.C.After a pause that coincided with AIPAC's opposition to Obama’s Iran nuclear deal, Sacks resumed his donations to AIPAC after the Hamas attack on Oct. 7, 2023, that killed 1,200 people in Israel, held 251 people hostage and triggered the war in Gaza.Sacks was one of the top 100 donors to the group’s affiliated political action committee in 2024. He continued his donations even as AIPAC has been heavily criticized for its defense of Israeli Prime Minister Benjamin Netanyahu and Israel’s offensive that killed more than 74,000 Palestinians through bombardment and famine in Gaza.Sacks defended his support for the group in an op-ed this spring, after AIPAC took heat for masking millions of dollars in spending in Illinois’ primary election through newly formed political action committees with innocuous names, to which Sacks also contributed.What brought Sacks, Emanuel togetherThe connection with Emanuel was forged through finance.When Emanuel left the Clinton White House, he returned to Chicago and took a job with an investment bank, Wasserstein Perella Co.But before he could parlay his political connections into a $16 million fortune, Emanuel needed to learn the finance business. He asked around about who could help, and was told to talk to Michael Sacks. Michael Sacks, right, appears with then-Mayor Rahm Emanuel and Deputy Mayor Mark Angelson at a press conference on the rooftop of City Hall. At the time, Sacks was vice chairman of World Business Chicago. Sun-Times file photo Sacks describes it as the professional version of a “blind date.”The two men quickly became friends and the friendship extended to their wives and children. When Emanuel decided to run for Congress after then-Congressman Rod Blagojevich decided to run for governor, Sacks was all in.The bond continued to build — even during Emanuel’s stint in Congress and as Obama’s first White House chief of staff. When then-Mayor Richard M. Daley chose political retirement over a race for a seventh term, Emanuel returned home to run for mayor. Once again, Sacks was all in.Sacks went on to become Emanuel’s top financial donor and major fundraiser.As mayor, Emanuel asked Sacks to lead World Business Chicago, the city’s public-private economic development agency. Emanuel also asked Sacks to join his Economic Council, and to advise him on economic development, finance and school funding.“He was like a $1-a-day adviser. He didn’t have an office at City Hall, but he was available — same way I would call Axe [David Axelrod] and Bruce Reed,” Emanuel recalls, adding that he and Sacks at times had “fierce disagreements.”Emanuel described Sacks as having served as the “tip of the spear" in the winning fight for an evidence-based school funding formula that has produced hundreds of millions in additional dollars for the Chicago Public Schools.That formula, passed over some objections from then-Republican Gov. Bruce Rauner, allows the CTU to now claim that the state “owes” CPS $2 billion.Securing evidence-based funding was a huge victory for education. No other Chicago mayor, not even Richard J. Daley, could achieve it. The uphill battle required Sacks to set up residence in Springfield. Also, there was Stacy Davis Gates, the CTU’s political and legislative director at the time.Sacks and the CTUSacks was pointed in his recollection of the CTU’s action and inaction during that fight.With $450 million in immediate funding to CPS on the line and more equitable funding going forward, the union was not doing anything to gather votes and, in fact, was “keeping the vote down,” he recalls.When crunch time came and the House roll call was still one vote short, now-convicted former Illinois House Speaker Mike Madigan “got up from the table and called Karen Lewis and said, `Karen, We are at 59. I need you to call Stacy and tell her to have [State Rep. Robert] Martwick flip his vote to yes,” Sacks recalls.Only then did the bill pass.But the fight left a bitter taste in the union’s mouth. Potter says there was a poison pill that the union blames Sacks for convincing lawmakers to swallow: private school vouchers. In conjunction with the new funding formula, lawmakers also approved a program called Invest in Kids. It provided 75% income tax credits to donors to private school scholarships that progressives have argued siphon funds from public schools.The union’s complaints about Sacks also include Emanuel’s decision to close 50 public schools in one fell swoop in 2013. Many of those shuttered schools remain empty today, and the neighborhoods around them have experienced higher crime and population loss.More recently, the union hasn’t been happy with Sacks’ decision to spend heavily to elect school board members opposed to their candidates, and to oppose CTU’s pick for school board president, Hilario Dominguez. Jackson Potter, vice president of the Chicago Teachers Union, speaks during a Chicago Board of Education meeting at Chicago Public Schools headquarters in the Loop March 30.Ashlee Rezin/Sun-Times “His relationship [to Chicago Public Schools] is largely colonial. Where is he from? He's from Highland Park. Does he have kids in Chicago Public Schools? No. So why is he spending all this money to control a system that's supposed to be democratically determined by the people who live here and send their kids to that system?” Potter says.Sacks counters: “Colonizer? My mom was a CPS teacher before Jackson Potter was born. I care about this election because I believe in public education and there is nothing more important to the future of our students and our city than the success of Chicago Public Schools.”Tension with Stacy Davis Gates buildsSacks says his tensions with Davis Gates started building in October 2024, when she began posting social media accusations that Sacks was a billionaire pushing a Trump 2025 agenda.In the months leading up to that point, Sacks had been making political donations to some of the leaders of Johnson’s emboldened Council opposition.Sacks said he called Davis Gates and asked what she was doing. She told him she believed he was involved with the fight the union was having with CPS CEO Pedro Martinez, who was refusing to bend to pressure from Davis Gates and Johnson to take out a loan to reimburse the city for a $175 million pension payment for non-teaching CPS employees.Sacks told Davis Gates that he had never met Martinez and was not at all involved in the loan fight, which ultimately got Martinez fired.But he also told Davis Gates that he had agreed to support a new organization called Common Ground Collective to help elect moderate Democrats to the Council and, ultimately, to play a role in school board races.Sacks told Davis Gates that he would contribute as much as $500,000 to the new group and warned her that, if she attacked him, he was prepared to spend even more. Chicago Teachers Union President Stacy Davis Gates speaks on behalf of the union during a rally outside CPS headquarters in the Loop, July 30.Candace Dane Chambers/Sun-Times “I told Stacy that I was not going to let her kick me out of the Democratic Party or Illinois without a fight,” Sacks said. “She seemed to be okay with me for a while after that.”The political detente was short-lived.By fall of 2025, Sacks had made another round of donations to Johnson’s council opposition and this time, anti-CTU school board candidates. And Sacks had become a political punching bag for the mayor, who accused the Chicago billionaire of being the driving force behind Johnson’s failed corporate head tax.The wealthy boogeymanSacks believes the decision to attack him was a calculated one. He claims that Pritzker was the CTU’s initial target.But Sacks says he believes the union subsequently determined that the governor was too popular with Chicago voters and decided to demonize the “wealthy Jewish guy” instead.“They have been attacking me with all kinds of lies and a lot of antisemitism since December — and as I told Stacy I would, I am fighting back. We will see how it goes,” Sacks said.Bill Daley, who succeeded Emanuel as White House chief of staff, says that, by attacking Sacks, the political tag team of Johnson and CTU is following a familiar playbook.“All socialists have a boogeyman who has money. It’s just a given,” Bill Daley says. Former U.S. Secretary of Commerce Bill Daley chats with supporters before the start of the Obama Presidential Center Grand Opening Ceremony on the South Side June 18.Ashlee Rezin/Sun-Times “He has what Brandon Johnson needs to make a boogeyman. He’s wealthy. He’s a businessman. And he’s Jewish. I’m not saying that Brandon is antisemitic. But the fact that [Sacks] is Jewish is a plus. It’s the cherry on top of the cake.”Potter, who is Jewish, scoffed at the notion that the mayor’s or union’s attacks are antisemitic.“Who's spending the most in school board races? Who's putting so much money behind Alexi Giannoulias? Who's putting commercials when you try to tax corporations?” Potter says. “It’s Sacks. He's put himself in the middle of all this.”State Sen. Robert Peters (D-Chicago), who is Jewish, sees Sacks as a “public figure” and scrutiny of him as legitimate. He said that the knee-jerk defense of Sacks by leaders of some Jewish organizations is part of a “watering down of antisemitism” that distracts from incidents of real antisemitic hate.“Sacks, who historically has not been very public, has become very public, and he is clearly not prepared for the sort of scrutiny that comes from that,” Peters said. “He seems to want to be able to apply an immense amount of scrutiny to a lot of people, but does not seem to handle that scrutiny on him very well.” Peters saw Sacks' enmity for Johnson firsthand during their one-on-one meeting last year. It was supposed to be about Peters’ campaign for Congress. Instead, Sacks spent most of the time talking about Johnson and the CTU.“I spent most of this meeting having to basically be like, ‘Okay, well, I'm not Brandon Johnson, and I'm not with CTU, and I don't know why we're talking about this,’” Peters said, adding it seems both sides are preoccupied with one another “while the city is facing crises.” Johnson puts Sacks in crosshairsOn the day he entered the race for a second term, Johnson attacked Sacks repeatedly and by name. When asked why, Johnson said “it’s very clear the role that he played in the Emanuel administration.”“Is he a source of pain? Ask the thousands of families that lost their public schools. Is he the source of pain? Ask the thousands of families that did not have access to public mental clinics,” Johnson said.In a statement for this story, a spokesperson for Johnson said the mayor has “been forced to respond to Michael Sacks and his super PAC, Common Ground Collective,” that has made “the progressive movement in our city a target.”Chicago Federation of Labor President Bob Reiter said Johnson’s portrayal of Sacks as an enemy of working people doesn’t jibe with the go-between role that Sacks has played on behalf of organized labor, in general, and working people, in particular.Reiter recalled that Sacks helped broker a settlement that ended a strike by downtown hotel workers and was “our advocate” and “someone we could go to… if we needed to get Rahm to lighten up on an issue.”“I don’t understand these attacks, and I don’t think it helps [Johnson’s] campaign. … There’s big corporations and billionaires who proudly say they’re against working people. … Michael has always been a supporter. He has always given back,” Reiter said.Johnson’s senior adviser Jason Lee told the Sun-Times that, as Emanuel’s closest adviser, Sacks “owns” all of the major decisions that Emanuel made.“You called me the mayor’s top adviser. And if I said to you ‘Anything that people don’t like, I had nothing to do with. I did not advise. Anything that’s good, that was me.’ You’d say, ‘That’s ridiculous.’ And you’d be right,” Lee said.“If somebody is the chief advisor, they have to accept responsibility for all the things that happened when they were in that role — whether that’s mass school closures, the cover-up of the murder of Laquan McDonald, whatever the case may be.” Lisa Schrader, who served as Emanuel’s chief of staff and now works for Sacks, branded Lee’s claim as “absurd.” Schrader said there was “no single person involved in every conversation or decision with Rahm, let alone Michael.” A helping hand for Kim FoxxIn the furor that followed the court-ordered release of the Laquan McDonald shooting video, Cook County State’s Attorney Anita Alvarez was defeated. Emanuel decided not to run for a third term as mayor. Kim Foxx was elected state’s attorney.But when Foxx found herself in trouble during a 2020 reelection campaign after pushing for criminal justice reforms, Sacks came to her aid with $1.1 million in campaign contributions. It happened over an egg breakfast. Then-Cook County State’s Attorney Kim Foxx speaks during a news conference at Chicago police headquarters in November 2024. Tyler Pasciak LaRiviere/Sun-Times “I said to him that it was going to be a very difficult campaign. I knew that there was a segment of the community, and particularly the business community — his friends and colleagues — who might have wanted a more traditional approach to criminal justice,” Foxx said.“He appreciated what I was trying to do. That he was translating to people, for me, what it was that I was trying to do to make the system more fair and equitable, and he said that he would support me.” Foxx first got to know Sacks during her days as chief of staff for Cook County Board President Toni Preckwinkle. At the time, Sacks was working on the Greater Chatham Initiative. She was impressed that a billionaire businessman would care enough to invest in a neighborhood that wasn’t his own. Emanuel has a long-standing policy of refusing to comment on his successor’s performance. But he made an angry exception in defense of his friend, Michael Sacks.“The attack says more about them than it does about Michael Sacks,” Emanuel said of the Johnson campaign. "If they were sitting pretty, they wouldn’t be talking about this. They’re not sitting pretty because of his leadership of the city, and everybody knows it, including the entire fifth floor. … There’s a pattern of a revolving door. That tells you something. It reveals something. Full stop.” ...read more read less