This weekend's endorsement from former President Donald Trump may have sealed the deal for front runner Darren Bailey.
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Jesse Sullivan hosted rally at Noon Whistle Brewing hoping to tap into any voters he can. Bailey is hosting his own rally in Des Plaines at 7 p.m., at a moment when it looks like it's his race to lose.
Bailey jetted around the state Monday, meeting supporters at airports including the Vermilion regional airport outside Danville.
Can Richard Irvin, Jesse Sullivan catch Darren Bailey?
A last minute endorsement from Trump at a downstate rally this weekend may have solidified his front-runner status and propels him to a primary victory.
"Well, I think the biggest difference is just awareness getting us but propelling us into national headlines," Bailey said. "People are aware, so now they're following it, even our own Twitter and Facebook and the messages that I am receiving there are people out there that just really were checked out."
Aurora Mayor Richard Irvin, the one-time front runner, spent Monday touring Forest City Gear, an aerospace gear manufacturer in Roscoe, outside Rockford, trying to win over employees who may not have voted yet. Irvin dismissed the Trump endorsement, saying Bailey is too conservative to win the general election in November.
"You need Republican votes, you need independent votes, and you need Democratic crossover votes," Irvin said. "Darren Bailey, no matter who he stands on the stage with, would not be able to get those independents and get those Democratic crossovers. I am the only one that will be able to get that."
Former Governor Jim Edgar worried about the down ballot impact of a Bailey primary victory.
"We would have the most right wing slate we've ever had going into the general election in Illinois, and I don't think that's good for the Republican Party in Illinois," Edgar said.
Sullivan also made a series of last-minute campaign stops, touting his own conservative credentials while attacking Bailey as the candidate Gov. JB Pritzker thinks he almost easily beat in November.
"I think we can, we're surging, there's so many undecideds just now making up their mind," Sullivan said. "We've also energized a whole group of people who have not voted in Republican primaries before but they're sick and fed up with how far left this governor has gone and want to fix the state."
Recent polls suggested there were still quite a number of undecided voters but whether it's enough for Irvin or Sullivan to catch Bailey is the question that will be answered Tuesday.