By John Gregory/Illinois Radio Network

CHICAGO – While a potential challenger to U.S. Sen. Mark Kirk (R-Ill.) questions his health, his Democratic counterpart in the Senate defends him.

In announcing he’s exploring a bid to challenge Kirk in the 2016 Senate race, William Kelly, a former candidate for Illinois comptroller and Mayor of Chicago, called Kirk “a disaster.” Going beyond criticizing Kirk’s comments and policies, Kelly talked about Kirk’s physical condition since he suffered a stroke in 2012.

“When I see them carrying Mark Kirk around, it’s like the political version of ‘Weekend at Bernie’s,’” Kelly said. “What is making it even more sickening is that our governor, Bruce Rauner, is the one who’s propping him and carrying him around and pretending that’s everything OK for his own political purposes.”

Kirk’s campaign declined to comment on Kelly’s remarks.

Despite recent controversial comments by Kirk, like referring to unmarried U.S. Sen. Lindsey Graham (R-S.C.) as a “bro with no ho,” he still has the public support of most Republicans. At a presidential campaign stop in Chicago Thursday, Graham himself said Kirk should continue his re-election bid.

“I am totally in Mark’s camp. He’s a good friend. He’s very knowledgeable on foreign policy. He’s a problem solver. He has supported comprehensive immigration reform. I think he’s got a lot to offer to the people of Illinois,” Graham said.

U.S. Sen. Dick Durbin (D-Ill.) feels Kirk has made it clear he regrets some of his recent remarks.

“Sen. Kirk has apologized for some of his comments, and I accept that. All of us in public life have said things we wish we could have say differently, but he’s made those mistakes. We disagree on some issues. We continue to try and find ways to work for the good of this state,” Durbin said.

Crain’s Chicago Business reported this week that frequent Republican donor and former candidate for governor Ron Gidwitz wanted Kirk to drop out of the Senate race. He later retracted those comments.