With the Illinois Republican Primary less than a week away, Chicago Mayor Rahm Emanuel is singling out presidential candidate Mitt Romney for what he sees as the former Massachusetts Governor’s weaknesses.

Emanuel, who was chief of staff under President Barack Obama and an adviser to former President Clinton, said Mitt Romney “lacks the fortitude” to handle the pressures of the White House.

“When you just take a look at the fortitude, the strength, the determination and the vision the president made on the auto industry and juxtapose to Mitt Romney, who doesn’t have the fortitude, the strength of the character, in my view, to stand up to Rush Limbaugh,” said Emanuel.

Emanuel was referring to a recent incident in which the conservative talk show host called Georgetown Law Student Sandra Fluke and “slut” and a “prostitute” after she testified in support of employer-covered contraception.

“In my view I thought what Rush Limbaugh said was absolutely not only wrong, but it was absolutely repulsive. That said, if you can’t stand up to Rush, how are you going to stand up to Russia,” said Emanuel.

Emanuel criticized Romney on in calls to let the U.S automobile industry fail in 2008.

Romney was the only candidate the mayor named outright Thursday at an unrelated press conference.

In a prepared statement, Romney’s campaign responded to Emanuel’s statements, accusing the White House of “dispatching its liberal allies.”

“President Obama can’t run on his disastrous economic policies or the historic loss of middle class jobs that has occurred on his watch. Americans won’t be fooled by falsse and negative attacks - they know that President Obama has failed, and they are eager to replace him with a leader like Mitt Romney who can turn around our struggling economy,” said a Romney aid.

A recent poll by the Chicago Tribune and WGN-TV showed Romney has a slight lead over Rick Santorum in Illinois.

Emanuel skirted questions about Democrats’ response to liberal comedian Bill Maher, who’s made controversial remarks about Republican Sarah Palin.

A pro-Barack Obama Super PAC reportedly took a $1 million donation from Maher.