WASHINGTON — The distance between health policy ideology and life-or-death health care narrowed to a few feet at a televised town hall meeting this week when a small-business man from Arizona stood up and faced House Speaker Paul Ryan.

“Just like you, I was a Republican,” Jeff Jeans began. Standing on the stage, the Wisconsin congressman broke into a grin as Jeans said he had opposed the Affordable Care Act so much that he had told his wife he would close their business before complying with that law.

But that, he said, was before he was diagnosed with a “very curable cancer” and told that, if left untreated, he had weeks to live. Only because of an early Affordable Care Act program that offered coverage to people with preexisting problems, Jeans said, “I am standing here today alive.”

The speaker’s smile vanished. His brow furrowed.

“Being both a small-business person and someone with preexisting conditions, I rely on the Affordable Care Act to be able to purchase my own insurance,” Jeans said. “Why would you repeal the Affordable Care Act without a replacement?”

Ryan went for the human touch. “First, I am glad you are standing here,” he replied. “I mean really. Seriously. Hey. No really.”

Jeans interrupted him: “I want to thank President Obama from the bottom of my heart, because I would be dead if it weren’t for him.”

The exchange during the CNN-sponsored town hall meeting Thursday encapsulated part of the challenge for Republicans as they begin to undo the health-care law under which 20 million Americans have obtained insurance coverage.

Hours after the House voted mostly along party lines Friday on a budget measure intended as the first step toward repeal, Jeans, 54, elaborated in an interview on his medical and financial crisis.

He had lost his health benefits, he told The Washington Post, when a company for which he had moved to Arizona filed for bankruptcy. Soon after, in early 2012, he was diagnosed with throat cancer. He offered to pay cash for the $30,000 treatment, but a cancer center near his Sedona home said he needed to produce either an insurance card or a $1 million deposit.

He could not. So Jeans was instead hospitalized for two weeks in an intensive care unit.

On April 1 of that year, he recounted, his wife bought an insurance policy for both of them through the Affordable Care Act’s preexisting condition insurance plan – a temporary program the law created before its insurance marketplaces began. That day, his cancer treatments began.

It was around that time that he left the Republican Party and created a Facebook page, “ObamacareSavedMyLife.”

Ryan assured Jeans that Republicans would not repeal the law without creating something new in its stead: “We want to replace it with something better.”