Speaker Michael Madigan announced Monday that he will appoint a special committee to review the case and recommend whether Blagojevich should be impeached. Once the committee makes a recommendation, the full House will decide whether to file impeachment charges against the governor.
"We're going to proceed with all due speed, but we're going to make sure that what we do is done correctly," the Chicago Democrat said.
Republicans and Democrats alike have called for Illinois lawmakers to begin impeachment proceedings against Blagojevich, saying the step is necessary to restore public confidence in state government.
"The General Assembly must move to impeach Rod Blagojevich immediately," said DuPage County State's Attorney Joe Birkett, a potential Republican candidate for governor in 2010.
Madigan did not join the chorus of officials calling for Blagojevich's resignation or say whether he thinks the governor should be impeached, saying he should remain neutral because he would preside over any impeachment debate.
But he did not back away from his role as one of the governor's harshest critics, saying he's not surprised by the federal allegations. Madigan, who once co-chaired Blagojevich's re-election campaign, often has refused to meet with Blagojevich or return his phone calls in recent months.
"I've had a chance to get to know Mr. Blagojevich over six years, so I was not surprised," Madigan said. "In light of what we've all seen ... how can anyone be surprised?"
Legislators met Monday afternoon for the first time since Blagojevich was arrested last week on charges he shook down businesses seeking state deals and tried to profit from his power to choose a replacement for President-elect Barack Obama's vacant Senate seat.
The legislative session's focus was supposed to be about considering a special election, but impeachment was the chief topic of conversation.
One survey shows 80 percent of state lawmakers support impeachment, reports CBS News correspondent Dean Reynolds.
Blagojevich spokesman Lucio Guerrero said the governor "has no plans on resigning Monday."
Guerrero didn't respond directly to whether the governor could or would do anything to slow down the Legislature's move toward impeachment.
"The governor has indicated in the past there is more to this story that he's wanting to tell at an appropriate time," he said.
The GOP plans to run television ads pressuring Democrats to approve a special election to replace Obama. Blagojevich still holds the power to appoint a new senator, and if he resigned, that power would go to Democratic Lt. Gov. Patrick Quinn.