"I have good news to report today. Sen. Kirk is doing very well. In fact, he's doing better than I expected he would be doing at this point," said Dr. Richard Fessler, neurosurgeon at Northwestern Memorial Hospital.
Over the weekend, the senator suffered a stroke and underwent surgery to relieve swelling on his brain. Kirk is expected to remain in intensive care for about another week.
Despite the good news, Sen. Kirk still appears to have a long road ahead to recovery.
The senator is said to be completely oriented and quick to follow commands. Kirk's biggest challenge to recovering from the stroke will be overcoming the physical damage.
"He asked for his Blackberry yesterday, so he's ready to go back to work," said Dr. Fessler. "He's breathing on his own. He's answering questions appropriately and quickly, so mentally he's doing very well."
Because the left side of his body was affected by the stroke, Fessler says the senator is speaking with a slight slur but indicated that will get better. For now, the important thing is that he's communicating, the doctor said.
"If we've just given him some sedation then it's more like a few words, if the sedation is wearing off then he speaks in longer sentences," said Dr. Fessler.
Physically, however, the news is not quite as good.
"He is moving his left side very little," the doctor said.
The senator is still in intensive care and Fessler said he will remain in serious condition for the next several days as he is still recovering from surgery that removed a four-by-eight inch portion of skull to relieve swelling on the brain.
"When the swelling goes down enough it's a simple enough procedure to go back and put it back on," Dr. Fessler said.
Fessler went on to stress that recovery will be a long process dependent on what Kirk's deficits turn out to be.
On Tuesday, ABC7 got an inside look at the state-of-the-art facility where the senator will likely undergo intensive in-patient rehab. The Rehabilitation Institute of Chicago provides in-patient care for an average of 150 patients, many of them stroke survivors like Dennis Reed and Walter Mason. Their strokes happened only two to three weeks ago and yet, they've already shown remarkable progress.
"I was unable to do anything on my left side," Reed told ABC7. "I didn't lose any strength or speech. I just lost balance, numbness."
"I've been very fortunate because my leg and my walking...I am walking again. Speech is back. We're still working on all the parts, but it's coming along," Mason said.
There was some talk earlier about whether the senator's lifestyle or diet several years ago may have been a contributing factor to his stroke. His surgeon said that Kirk was very healthy previous to the stroke. He said that in this case the stroke was "one of those unfortunate disasters that sometimes happen to people."
Statement from the Family of Senator Mark Kirk
"We are overwhelmed by the outpouring of support we've received over the last couple of days -- from President Obama, Leader McConnell, Senator Durbin, Governor Quinn, Mayor Emanuel, the Illinois delegation and so many others across the state, the nation and beyond. Words cannot describe how much Joe Manchin's friendship and support means to us and especially to Mark. We are truly blessed to have such amazing family and friends."