LITTLE ROCK — Spokespeople for Arkansas’ senators, Republicans John Boozman and Tom Cotton, said Thursday afternoon the senators were reviewing the Senate health-care bill unveiled that morning and did not say whether they intended to vote for the measure.

The bill, hammered out behind closed doors by a group of senators said to include Cotton, cannot pass if more than two GOP senators oppose it, assuming it receives no Democratic support. But four Republican senators, Rand Paul of Kentucky, Ron Johnson of Wisconsin, Ted Cruz of Texas and Mike Lee of Utah, said in a joint statement Thursday they are “not ready to vote for this bill.”

The four said they are open to negotiations on the measure, however.

The 142-page bill could receive a vote on the Senate floor next week. Republicans hold a 52-48 advantage over Democrats in the Senate but could pass the bill in a 50-50 tie that presumably would be broken by Vice President Mike Pence.

The Senate bill, a modification of the bill the House passed last month to repeal and replace the federal Affordable Care Act, would limit federal subsidies for health insurance to people earning between 100 percent and 350 percent of the federal poverty level, instead of 100 percent to 400 percent as the ACA provides.

Like the House bill, the Senate bill would allow insurers to charge older people five times as much as younger people, instead of three times as much under the ACA.

Also like the House bill, the Senate measure would shift some Medicaid costs from the federal government to the states and would phase out federal funding for the Medicaid expansion that the ACA made possible for Arkansas and other states.

More than 300,000 Arkansans have obtained health-care coverage under Arkansas’ hybrid Medicaid expansion program, which provides government-subsidized private health insurance to people earning up to 138 percent of the federal poverty level.