Four Senate Republicans introduced a health-care plan on Monday that promises states a buffet of options for providing health insurance, including keeping their Affordable Care Act exchanges.

The proposal, sponsored by Sens. Bill Cassidy (R-La.), Susan Collins (R-Maine), Shelley Moore Capito, (R-W.Va.) and Johnny Isakson (R-Ga.), comes as Republican leaders are under pressure to explain how they will prevent more than 20 million people from losing insurance if the GOP makes good on plans to repeal former president Barack Obama’s signature health-care law.

The group is pitching a plan that would repeal federal mandates that require individuals and business owners to buy insurance, shifting health-care decisions to governors and state legislatures. The GOP plan would allow people to keep the plan in place today.

“If you like your insurance you should keep it, and we mean it,” Cassidy said Monday.

The proposal is one of many GOP-written alternatives expected to be released in coming weeks as the party scrambles to avoid criticism for repealing the ACA without a viable replacement. Many of the proposals include similar elements, such as shifting the burden of administering insurance coverage to states through block-grant-style funding, and an emphasis on individual health savings accounts.

The true test of any of these plans will be how they are received by President Trump, who has said he wants to see insurance for everyone.

Collins told reporters that the plan is “still a work in progress” but that the goal is to let states decide whether they want the current system of state and federal insurance exchanges, new state-run marketplaces with tax-credit-funded health savings accounts or no federal funding at all. Every state would have access to the same level of funding that is available through the ACA — plus any money that would have been provided from Medicaid expansion, regardless of whether the state actually expanded that government program.

“With this legislation, we are placing a specific replacement proposal on the table for our colleagues to coalesce around, debate and refine so that our efforts can move forward with no gap in coverage for those relying on the current system,” Collins said.

The senators said they also want to keep key benefits — such as a ban on insurers denying coverage based on preexisting conditions, allowing adult children to stay on their parents’ plan until the age of 26 and free coverage for preventive care such as mammograms and childhood vaccines. The catch: To pay for all of the benefits, they also need to keep the ACA taxes that Republicans have maligned.

Cassidy said he would prefer to fix the tax portions of the law later this year when GOP leaders plan to undertake a comprehensive overhaul of the tax code. A tax overhaul is far from a certainty, but Cassidy said retaining the taxes, at least temporarily, is the only way to pay for the ACA benefits the GOP has promised to maintain.

“President Trump has said he wishes to cover all, take care of those with existing conditions without mandates,” Cassidy said. “For that you need revenue. Bottom line.”

Cassidy and Collins said they hope their plan will attract some support from Democrats. But Senate Minority Leader Charles E. Schumer (D-N.Y.) dismissed it immediately.

“Under their proposal — which, if it is the Republican replacement plan, is a far cry from the full replacement plan they have promised for years — millions of Americans would be kicked off their plans, out-of-pocket costs and deductibles for consumers would skyrocket, employer-based coverage for working families would be disrupted, and protections for people with pre-existing conditions, such as cancer, would be gutted,” Schumer said in a statement. “It is nearly impossible to keep the benefits of the Affordable Care Act without keeping the whole thing.