CHICAGO (WLS) -- The speculation is over as Chicago billionaire J.B. Pritzker made his run for Illinois governor official Thursday.
He is an investor, philanthropist, Democratic fundraiser and now gubernatorial candidate. Pritzker joins a crowded field of candidates ready to take on Governor Bruce Rauner.
"Do you know why I'm running for Governor? Because everything is under siege by Donald Trump and Bruce Rauner," Pritzker said.
Lumping Bruce Rauner with President Donald Trump is a strategy J.B. Pritzker is taking as he formally announced his candidacy for governor. He may be worth more than $3 billion, but Pritzker does not think his wealth will turn off the Democratic base.
"I'm very different from the governor. I am who I'm a genuine progressive governor for everyone," he said.
Pritzker says he has no plans of dropping his G's or wearing flannel shirts. The 52-year-old has been involved with politics his whole career, donating millions to Democratic causes and candidates. Republicans say Pritzker is another Michael Madigan puppet who wants to raise income taxes.
"We've got to tax millionaires and billionaires, we're not going to tax middle class families we've got to get people to pay their fair share," Pritzker said.
Looking for more support from the African-American community, Pritzker made his announcement on the South Side in a Chicago Park District field house.
He is already getting some union and City Hall support. 47th Ward Alderman Walter Burnett believes Pritzker has what it takes to go head to head with Rauner.
"He is the only one who has the resources to be able to compete with this governor to run for office, you've got to fight fire with fire," Burnett said.
Pritzker joins a field of Democrats that includes multimillionaire Chris Kennedy. While Pritzker says the campaign is all about beating Rauner, he must get through what could be a tough primary first.
"You have two wealthy titans with name recognition who have ambition I think they are going to tear each other apart," said ABC7 Political Analyst Laura Washington.
Democratic candidates State Sen. Daniel Biss and Chicago Alderman Amaya Pawar both have welcomed Pritzker to the race.
"I welcome the debate about whether the future of the Democratic Party will be a vehicle for the very rich and machine politicians or one for the rest of us," Biss said.
"J.B. Pritzker is an accomplished investor and philanthropist and I welcome him to the race for governor," Pawar said.
Also in the Democratic race is downstate school Superintendent Bob Daiber. Chicago Treasurer Kurt Summers it thinking about running.
An heir to the Hyatt hotels fortune, Pritzker was recently ranked by Forbes magazine as the third-wealthiest person in Illinois, with an estimated net worth of about $3.4 billion. That easily makes him the wealthiest person running, though Rauner - a multimillionaire who put $50 million into his campaign fund late last year - also has received millions in campaign contributions from Illinois' richest person, businessman Ken Griffin.
Outside groups already have been active in the 2018 contest as well. Last month, a group affiliated with the Republican Governors Association began airing campaign-style ads featuring Rauner. In them he talks up his efforts to improve Illinois' business climate and enact changes such as term limits for lawmakers.
The ads come as Rauner and the Democrat-controlled Legislature have been unable to agree on a state budget for nearly two years, leading to major cuts to social services, colleges and other programs.
Illinois Republican spokesman Kirsten Kukowski released a statement saying, "Political insider J.B. Pritzker is the financial muscle behind Mike Madigan's political machine, funneling over a million dollars to help him in just the last year. And like Madigan, Pritzker wants to hike the income tax to over 5 percent without any fixes to repair Illinois. One can only imagine the devastation Mike Madigan could do with a lapdog billionaire at his side. Pritzker puts the insiders first and the taxpayers last."
Pritzker - whose full name is Jay Robert - is the founder of Pritzker Group, a venture capital firm that focuses heavily on the technology sector. He also founded 1871, a Chicago hub for tech startups. He previously served as chairman of the Illinois Human Rights Commission, and he is a vocal advocate for early childhood education, a cause to which he and his wife have donated significant amounts of money.
His sister, Penny Pritzker, served as Commerce Secretary under former President Barack Obama.
The Associated Press contributed to this report