Trump's Granite City appearance is his first visit to Illinois as president.
"It's curious, isn't it, that a president of his own party is here in Illinois, but Donald Trump and Bruce Rauner are not together," said Democratic candidate for Governor JB Pritzker.
Pritzker has used Rauner's silence on Trump as an on-going campaign issue, accusing Rauner of attempting to play to both sides.
"He stands with Mike Pence and extols the virtues of the Trump administration on one hand, but on the other hand, he is unwilling to go to Granite City and stand with the president," Pritzker said.
Rauner appeared with Pence at an event in Rosemont July 13. At an event in Itasca Thursday, Rauner refused to answer questions about Trump or the president's Granite City appearance.
Republican candidate for Illinois Senate in the 23rd District Seth Lewis, who also attended the Itasca event, said he sympathized with Rauner's position on the Trump issue.
"I understand where the governor is at," Lewis said. "In Illinois many don't like President Trump, and the governor is in a tough race. He needs to focus on Illinois, not Washington politics."
Rauner also attended events in Rockford and Peoria Thursday.