J. B. Pritzker defeated Bruce Rauner in the 2018 general elections. Rauner was a Republican governor who was running for re-election, while Pritzker was a Democrat who had never held elected office before. Pritzker won the election by a wide margin, receiving over 54% of the vote to Rauner's 43%.
Mastering the Rauner Chronicles: Exploring the Legacy of Bruce Rauner as Governor of Illinois