SAN FRANCISCO (CBS SF) — His voice still weak and raspy from spending weeks on a ventilator, East Bay Congressman Mark DeSaulnier took to social media to thank the public their prayers and talk about his harrowing brush death while battling pneumonia.

Rep. DeSaulnier (D-Concord) said his life changed during March 4 evening run.

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“Early March — March 4th, I went out a run here in (Washington) D.C., one of my sons was talking about maybe running his first marathon and as some of you know I always enjoyed running, I’ve run 23 marathons, Boston, New York,” he said. “So I was trying to get my miles up. I took a wonderful run from my home here on Capitol Hill down to the Lincoln Memorial… On the way home, I was crossing an unique phenomena in D.C. — a five-intersection road — and the light was starting to change.”

“I had built my speed up and I was pretty proud of myself so my adrenaline was up, I sort of kicked it in to get through the intersection and I took a fall. For those of you into distance running, stumbling and falling is not unusual. The biggest damage is usually to your ego or your palms when you reach out to brace yourself.”

“In this instance, unfortunately, I was carrying my cellphone in my right hand…I tucked my elbow as a flew through the air and landed on my ribs.”

DeSaulnier broke multiple ribs and injured his spleen in the fall.

The congressman was able to make it to his nearby home and put ice packs on his injured ribs. He went to the doctor the next morning and discovered the extent of his injuries.

But things took a turn for the worse as he was home rehabilitating.

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“By the 14th, my lungs were filled with pneumonia,” DeSaulnier said. “Your lungs become more susceptible to this with age and because I suffer from cancer, as some of you know, you immune system is somewhat weakened.”

He was immediately hospitalized and the battle for his life intensified as the days went by. He was tested for COVID-19, those tests came up negative. DeSaulnier remained on the ICU for nearly five weeks and at one time was given just a 10 percent chance of survival.

The congressman spent four weeks on a ventilator.

“On a key night, my doctors called my sons and told them my organs were breaking down and there was little they could do,” he said. “They wanted to try a medical procedure to try and take pressure off my organs. They did it and the next day my sons were expecting a phone call from the hospital to say I had passed away in the night. Instead, they got a phone call saying I was a little bit better.”

DeSaulnier said he got better each day and was finally allowed to return to his Washington home the first week in May.

“I am very grateful and can’t tell you what kind of impression this leaves on someone,” he said. “Cancer was amazing enough, but I am so grateful every day.”

DeSaulnier is up for re-election in November and said he’s still in that race. He has represented California’s 11th congressional district, which includes most of Contra Costa County, since 2015.

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According to the biography on his congressional website, DeSaulnier is described as an avid runner, who has completed 21 marathons.