The Center on Budget and Policy Priorities said Graham-Cassidy "would give states broad waiver authority to eliminate the ACA's core provisions for people with pre-existing health conditions."
The group noted those waivers would come on top of the bill's elimination of federal aid to help low- and middle-income people buy individual health plans, the elimination of expanded Medicaid benefits to poor adults, and big cuts to overall health insurance spending by the government.
CBPP senior fellow Aviva Aron-Dine wrote that a "little-noticed provision" of Graham-Cassidy that is related to block grant funding to states would allow individual states to get rid of Obamacare's pre-existing rules.
"For example, a state that used a small portion of its block grant funding to provide even tiny subsidies to all individual market plans could then waive these protections for its entire individual market," Aron-Dine wrote.
"Likewise, states that used block grant funding to offer or subsidize coverage for low-income people could offer plans with large gaps in benefits. States seeking waivers would have to explain how they 'intend' to maintain access to coverage for people with pre-existing conditions, but they wouldn't have to prove that their waivers would actually do so."
Aron-Dine noted that the waiver authority in Graham-Cassidy is similar to waivers contained in an Obamacare replacement bill passed by the House of Representatives earlier this year.
A Congressional Budget Office analysis found that states that contain one-sixth of the nation's population would let insurers charge sick people higher rates under those waivers in the House bill.
In those states, "less healthy individuals (including those with preexisting or newly acquired medical conditions) would be unable to purchase comprehensive coverage with premiums close to those under current law and might not be able to purchase coverage at all," the CBO said.
And states accounting for half of the U.S. population would let insurers exclude the Obamacare requirement that their health plans cover a minimum set of so-called essential health benefits, the CBO found.
People needing, "maternity care, mental health and substance abuse benefits, rehabilitative and habilitative services, and pediatric dental benefits" in those states "would face increases in their out-of-pocket costs," according to the analysis.
"Some people would have increases of thousands of dollars in a year," the CBO said.