(CBS) — Republican candidates for governor in Illinois’ upcoming primary election turned on each other Wednesday night.

At one point, the candidates were allowed to ask a question of one other. Front-runner Bruce Rauner chose State Senator Kirk Dillard.

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“Why are you running in the Republican Primary? I think you should be running in the Democratic Primary. You’ve taken more government union money. Those are exact same groups… that have helped get us in the financial mess we’re in,” Rauner said to Dillard.

Dillard responded saying, “Mr. Rauner doesn’t quite get it and this is one of many things that make him unelectable, that a third of these people that he likes to demonize are Republican Primary voters,” said Dillard.

Mr Rauner and his money machine that’s spent records framing his image was another key.

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“Why should the voters of Illinois trust Bruce Rauner, someone that they didn’t even know months ago, just because he spent 6-8 million dollars of his own wealth,” said State Senator Bill Brady.

For the first time though, Mr. Dillard has a TV spot in part paid for with union money he admits.

“Mr. Dillard is part of the problem in Springfield and it’s the reason I’m running for governor,” said Rauner in the debate.

Dillard said putting Rauner in charge, “is like putting a rat in charge of the cheese.”

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Leader Bruce Rauner is concerned that despite his millions spent, more than a quarter of voters are still undecided. CBS 2 wanted to ask him that but he did not attend the post debate Q and A with reporters. Only Senators Brady and Dillard did.

Brad Edwards