Incumbent Republican governor Bruce Rauner ran for re-election to a second term in office,[1] but was defeated by Democratic nominee JB Pritzker.

Rauner was one of two incumbent Republican governors to be defeated for re-election in 2018, the other being Scott Walker in neighboring Wisconsin, who had lost narrowly to Tony Evers.

[4][3] Local officials A November 2017 Capitol Fax/We Ask America poll found that 83% of Republican voters had never heard of Ives.

"[37] Rauner largely ignored his opponent and focused on attacking Speaker Mike Madigan, comparing him to his likely Democratic challenger, J.

[40] Ives released an ad titled "Thank You, Bruce Rauner" on February 3, 2018, in an attempt to challenge her opponent's commitment to conservative values.

Her ad featured actors outfitted to portray a transgender woman, an anti-fascist protester wearing a hood and a bandana over his face, a member of the Chicago Teachers Union and a Women's March activist.

By comparison, in 2014 Rauner only received 40.2% of the primary vote in his narrow win victory over Kirk Dillard, Bill Brady, and Dan Rutherford.

In 2018, Rauner did well in central Illinois compared to the Republican primary four years earlier, when he managed 30% in the downstate region and finished 2nd to Kirk Dillard.

Whitney Young High School hosted the first student-run gubernatorial debate in the United States on October 4, 2017.

All seven then-current candidates attended, meaning Daniel Biss, Bob Daiber, Tio Hardiman, Chris Kennedy, Alex Paterakis, Ameya Pawar, and JB Pritzker.

[185] The Illinois chapter of progressive advocacy organization Our Revolution sponsored a forum at the Chicago Teachers Union headquarters on October 8, 2017.

Candidates voiced similar opinions on single-payer health care, gun control, and the minimum wage, but differed on a hypothetical state deal with Amazon and relationships with powerful Illinois Speaker Mike Madigan.

"[193] Another debate took place on March 14, revolving around topics including Pritzker's newly reported offshore holdings, Illinois House Speaker Mike Madigan, and education.

This last occurred in 2006, when Rich Whitney won 10% of the vote, allowing the Illinois Green Party to achieve such status.

[208] Sam McCann, a longtime intraparty opponent of Bruce Rauner, resigned from the Republican Caucus to run for governor as a member of the newly created Conservative Party.

[231][232] Following his surprisingly narrow primary win, Rauner offered former state senator Karen McConnaughay, attorney general nominee Erika Harold, Chicago Cubs co-owner and Republican National Committee Finance Chair Todd Ricketts and Illinois Republican Party Committeeman Richard Porter the chance to replace him on the ticket, with the promise that he would continue to fully fund the campaign using his personal wealth.

[233] Rauner consistently trailed Pritzker in the polls by large margins, and the race was rated as a likely Democratic win by all major election prognosticators.