Millionaire businessman Willie Wilson, 70, attended the New Covenant Missionary Baptist Church on Sunday and told local reporters that his visit was nothing more than "one of the biggest property tax relief assistance" events of the year.
He denied he was attempting to buy votes.
Meanwhile, Illinois governor Bruce Rauner has been forced to defend attending the church on the same day to speak during the service.
He rejected claims by opponents that he was also trying to buy votes for his own re-election as governor and said to AP that he was as surprised as the congregants by Wilson's actions.
"I think the idea of handing out cash if you're a candidate for office is outrageous," Rauner said.
"It should not happen."
The Illinois State Board of Elections said in a statement that Wilson didn't break any campaign finance laws because the money came from his non-profit foundation - not his campaign fund.
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