Sen. Mark Kirk (R-Ill.), center right, gets help from Vice President Biden, right, and Sen. Joe Manchin (D-W.Va.) ascending the Capitol steps on Jan. 3, his first day back in the Senate after suffering a stroke in 2012. (Chip Somodevilla/GETTY IMAGES)

Mark Kirk is the junior senator from Illinois.

“Am I going to die today?” I asked Jay as we rode together in an ambulance through the streets of Chicago. Jay Alexander was my doctor but also my friend, and I knew he wouldn’t lie. “Just give me a percentage,” I pleaded.

“There’s a 98 percent chance you’re not going to die today,” he said.

It wasn’t the way I expected my day to go, but as soon as I’d felt dizzy and experienced numbness in my left arm that Saturday morning, Jan. 21, 2012, I knew I was in trouble. An MRI soon discovered that the inner lining of my carotid artery had peeled away. The dissected artery was blocking the blood flow to my brain, putting me in imminent danger of a stroke.

Anticoagulants kept my blood pressure down, and for a few hours I seemed to stabilize. But then the numbness and tingling on my left side worsened, and my vision got blurry.

Jay, who had met me at the emergency room at Northwestern Lake Forest Hospital, ordered me transferred to Northwestern Memorial Hospital in Chicago, which has a certified stroke center. It was on the way there that he gave me my chances and assured me that, given my age and health, my chances for recovery from a stroke were good.

I was in my hospital bed when the waves came and I began to lose control of my body and mind. Unbelievable, I thought. I’m only 52. I didn’t even know anyone who’d had a stroke.

More than a week later, I regained a confused consciousness in the intensive care unit. I knew I was lying in a bed. I thought someone was sharing the bed with me, but it was my own leg. I vaguely remember a party the ICU staff had for the Super Bowl and the smell of the food they brought.

I had two operations to relieve the swelling in my brain and remained at Northwestern Memorial until Feb. 10, when I was transferred to the Rehabilitation Institute of Chicago (RIC). In all that time, I remember only one rational thought: I needed to get out of there and back to reality, back to my job serving the people of Illinois, which has always been the greatest ambition of my life.

I still worried I would die. I dreamed that three angels came into my room and wanted me to go with them, but I said no because I knew where I was, on the ninth floor of the RIC, and why I was there: to begin a long, difficult recovery from an ischemic stroke.

When you’ve been flat on your back for weeks, your circulatory system doesn’t respond well the first time you try to get up. The therapists at the RIC were prepared for that. They strapped me on a table and tipped it upright. I passed out immediately. When I came to, I realized how hard a recovery I faced if I couldn’t even stand up.

I had blood clots in my leg that were treated with anticoagulants. I asked a doctor what would happen to me if one of the clots broke loose. “You could have a pulmonary embolism,” he answered, “and you would die.”

At best, I thought it unlikely that I would recover enough to return to the Senate. I had always been a glass-half-empty kind of guy, a believer in Murphy’s Law.

The staff at the RIC consider that kind of attitude debilitating, and they don’t tolerate it in their patients. My physical therapist, Mike Klonowski, was a tyrant and, God bless him, a great inspiration. The stroke had severely impaired my left leg, but Mike expected me to walk again. He would teach me how to do it, or we would both die trying.

One day he pulled me into a seated position on my bed, but I couldn’t stay upright. He kept pulling me up, and I kept falling over. “Give me a second, will you,” I snapped. “I’m about as weak as you can get.” But whenever I thought I couldn’t do anything, Mike and everyone at the RIC always answered, “You will be able to.”

He had me on the treadmill as soon as I could manage. I regarded my left leg as a lifeless appendage. Mike kept insisting that it would bear weight. The moment I realized that it would, and that I could swing it from my hip and propel myself forward, was the breakthrough revelation of my rehabilitation.

Kept upright by a track and a harness, I wanted to run down the hallway that day — and tried. But Mike stopped me and told me that slow walking was more instructive to my brain. I disagreed; we had a screaming match. He prevailed.

Hour after hour on that infernal machine, trying to do a simple thing that my brain would no longer communicate to my limb, was torture. Once, during an exhausting session, I threw up on Mike. He just looked up and said, “I can’t believe you did that to me.”

I wanted to give up almost every day. I was indescribably fatigued. I wanted to sleep all the time, a common desire in stroke sufferers. But I was beginning to believe. I used the prospect of returning to work, of climbing up the steps of the Capitol and walking the 50 paces to the Senate floor, as motivation. With every swing of my leg on the treadmill, I became more convinced I would do it.

Once, when I was a little down in the dumps, the RIC chaplain read to me from the Gospel of Matthew, Chapter 6: “Consider the lilies of the field, how they grow; they toil not, neither do they spin: And yet I say unto you, that even Solomon in all his glory was not arrayed like one of these. Wherefore, if God so clothe the grass of the field, which today is, and tomorrow is cast into the oven, shall he not much more clothe you, O ye of little faith?”

I’m different from what I was. My left leg and left arm might never work like they once did, but my mind is sharp. I’m capable of doing the work entrusted to me by the people of Illinois, but I am forever changed.

I’m an optimist now, grateful for every blessing. Bad things happen, but life is still waiting for you to make the most of it. I want my life to count for something more than the honors I once craved. I believe it will.

My faith is stronger. My humility is deeper. I know I depend on family and friends more than I ever realized. I know, too, that the things that divide us in politics are infinitesimal compared with the dignity of our common humanity.

Climbing the steps of the Capitol on Jan. 3 was one of the greatest moments of my life. It was a goal fulfilled and a message to all stroke survivors: Never, ever give up.

I was the beneficiary of many kindnesses from colleagues on both sides of the aisle after my stroke, and those acts will forever matter more to me than any political differences. I don’t expect to be the same senator I was before my stroke — I hope to be a better one. I want to make my life matter by doing work that matters to others. I want to do it with the help of my friends, Republicans and Democrats, and to share the satisfaction of knowing we have honored our public trust together.

I was once a pessimist. I’m not that man anymore. And that change, brought about by misfortune, is the best thing that ever happened to me.

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