Republicans may introduce another plan to repeal and replace Obamacare as early as Wednesday.
Senators Bill Cassidy, R-La., and Lindsey Graham, R-S.C., wrote the bill, which relies on block grants to the states.
"Take the money and power out of Washington, the same amount of money we would have spent on Obamacare, and let states design the systems," Senator Graham said.
Critics say the proposal would give states a chance for a waiver that could eliminate the requirement to cover pre-existing conditions.
It will be a close vote. Several Republican senators spoke out against the plan, including Senator Susan Collins of Maine, who said safeguards for americans need to be stronger.
To entice senators on the fence or voting no, a revised Graham-Cassidy plan will be unveiled Monday giving more money to hold-out states.