Nearly 40 percent of Idahoans have pre-existing conditions that would prevent them from obtaining health insurance were it not for the Affordable Care Act, the group “Close the Gap” reports today. It drew the statistic from federal data from the U.S. Department of Health and Human Services that shows that 662,319 Idahoans had pre-existing conditions prior to the start of the ACA, also known as Obamacare.

The group, which supports closing Idaho’s coverage gap that currently leaves 78,000 residents of the state without health insurance they can afford, because they make too much to qualify for Medicaid and too little to qualify for subsidized insurance through the state insurance exchange, is warning that proposed health care changes being debated in Congress could move more Idahoans into the gap, by allowing states to decide whether or not to require insurers to cover people with pre-existing conditions; allowing insurers to impose annual and lifetime limits on coverage that the ACA prohibited; and removing requirements for “community rating,” which prevents insurers from charging sick people more.

Lauren Necochea, director of Idaho Voices for Children, and Luke Cavener of the American Cancer Society’s Cancer Action network Idaho both said the changes could mean serious problems for Idahoans including children and people with cancer.

Necochea said Idaho Rep. Mike Simpson co-sponsored legislation in February entitled the “Pre-Existing Conditions Act” that would prohibit insurers from charging people more based on health status, but the bill hasn’t advanced. “We encourage Congress and the rest of Idaho’s delegation to follow Congressman Simpson’s lead … to maintain these protections,” she said.

The group’s statement comes the morning after late-night TV talk show host Jimmy Kimmel gave an emotional 13-minute opening monologue in which he revealed his newborn son’s severe heart defect and emergency surgery, which was successful, but follow-up surgeries will be required. Essentially, he said, his son was born with a pre-existing condition. In tears, Kimmel urged continued protections for Americans with pre-existing conditions, saying, “No parent should ever have to decide if they can afford to save their child’s life. It just shouldn’t happen. Not here.”