Current polls show Republican Darren Bailey has the frontrunner for Illinois governor but some political analysts say Tuesday’s primary is still up for grabs in what could be a very tight race.

A large number of undecided voters could cause a shift when the ballots are recorded on June 28.

Republican strategist Stephanie Hitt believes the race is tighter than polls would indicate.

“I hear Bailey’s name, but I still hear Irvin, I still hear Sullivan,” Hitt said. “I hear those names almost as frequently as Bailey on the ground.”

Ogden and Fry polled about 500-likely Republican voters. About 37% supported Bailey. Jesse Sullivan came in second. Aurora Mayor Richard Irvin finished third.

Twenty percent were undecided.

When pollsters asked the voters if they had to choose today, Bailey again finished on top followed by Irvin and Sullivan.

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This weekend, Trump endorsed Republican Darren Bailey for governor of Illinois.

Hitt says don’t count out Irvin, the early frontrunner thanks to billionaire Ken Griffin, who donated $50 million to his campaign. The political analyst also says venture capitalist Sullivan of central Illinois could be the dark horse in the race.