[W]ASHINGTON — Hours after a last-ditch effort to repeal Obamacare was derailed, four senators faced off on CNN over health care reform.

Republicans Bill Cassidy, of Louisiana, and Lindsey Graham, of South Carolina, touted their proposal, which features reductions in Medicaid payments to states and the repeal of mandates under the Affordable Care Act.

Sen. Amy Klobuchar, D-Minn., and Sen. Bernie Sanders, I-Vt., defended Obamacare and promoted a universal health care system.

The hour-and-a-half-long debate was held shortly after Sen. Susan Collins, R-Maine, announced she would not support Graham and Cassidy’s bill. With her dissenting vote, Republicans fell short of the 50 votes needed for passage.

Graham said they weren’t giving up.

“We’re going to press on,” he said.

Cassidy and Graham pitted their proposal against Sanders’ vision for a single-payer health care system.

Sanders insisted that his Medicare-for-all proposal, which is unlikely to be considered by the Senate, is not “radical.” Recognizing that his dream of a single payer system is a long way off, however, Sanders said the current health care system under Obamacare should be stabilized.

“What the American people want is us to work together to build on and improve the Affordable Care Act, not repeal it,” Sanders said.

Cassidy fired back: “Going to a single-payer system is not building upon and improving.”

Early in the debate, Sanders seized on comments Graham said that insurance companies are “the biggest winner” under the Affordable Care Act.

“Lindsey is right,” Sanders said.

Graham responded by denouncing the Vermont senator’s Medicare-for-all proposal.

The four senators complained about the high cost of prescription drugs, but differed over how to solve the problem.

They clashed over other issues. Graham and Cassidy defended a provision in their bill that would have allowed states to choose whether to require insurers to cover people regardless of pre-existing conditions.

They also differed over funding for Planned Parenthood. Klobuchar said coverage for women’s health is essential, while Graham and Cassidy defended restrictions on funding for abortion services.

Klobuchar dismissed the polarizing partisanship over reform approaches as a “false choice.”

“It’s not just between one or another, there is a middle ground here of things we can do to fix it,” she said.

An effort in the Senate to stabilize the insurance markets had stalled, she said, because Graham and Cassidy’s bill “took up all the oxygen.”

Twitter: @emhew. Elizabeth Hewitt is the Sunday editor for VTDigger. She grew up in central Vermont and holds a graduate degree in magazine journalism from New York University.