Today he spoke about health care with far less bravado.
"I voted against it, but we lost," Kirk said Tuesday at an event at Larson Forgings. "My job is to explain how this will affect voters."
Kirk backed off his repeal theme as the Giannoulias campaign released an ad goading him to get started.
The Giannoulias ad encourages Kirk to clarify his statements in public and plays on Obama's "Go For It" quip from last week. It also includes a segment from Rachel Maddow when she calls the congressman out by name on her cable program.
"Really Mark Kirk, you want to lead the effort to restore the insurance industry's right to deny coverage to kids who have preexisting conditions?"
Kirk today said he simply wants to make sure everyone in Illinois knows about the taxes associated with the new federal legislation, especially with proposed taxes that could come down locally.
"I'm concerned about double whammy with the governor's planned tax increase," Kirk said.
While he was backtracking, however, Kirk sent a shot toward Giannoulias' camp imploring him to clear up a campaign issue and speak plainly about his family's troubled bank.
"When the Broadway Bank collapses on April 23rd will Alexi come clean?" the congressman asked.
Giannoulias didn't immediately respond.