The Republican sponsor of a last-gasp effort to tear down the Affordable Care Act (ACA) said on Tuesday that he had “never felt better” about the chances of repealing the 2010 law.

The new bill, authored by Republican senators Lindsey Graham – who expressed his optimism – and Bill Cassidy, comes as the White House and GOP leaders push for a showdown vote on the repeal package by the end of the month.

The renewed effort revives a seven-year drive to dismantle the ACA, Barack Obama’s signature legislative achievement, which extended coverage to more than 20 million peopletwo months after a previous repeal bill fell one vote short in the Senate.

That effort was given a jolt this week when the Graham-Cassidy bill – considered improbable two weeks ago – began attracting support from congressional Republicans and, notably, the president.

Now Senate Republicans are under increasing pressure and an imminent deadline to pass the latest repeal measure.

In a show of support, the vice-president, Mike Pence, shuttled between New York to Washington to attend a weekly caucus lunch on Capitol Hill on Tuesday, in between meetings related to the annual United Nations general assembly session. Before the lunch, Pence told reporters aboard Air Force Two that his pitch to Republicans was simple: “This is the moment, now is the time. We have 12 days.”

Reconciliation, the process that allows lawmakers to pass budget legislation with a simple majority, expires on 30 September. After that, budgetary legislation must clear a 60-vote threshold. Democrats agree the law has problems but have so far remained unanimously against repeal.



This is the moment, now is the time. We have 12 days Mike Pence, US vice president

The Republican healthcare bill would transfer billions of dollars of federal spending under the ACA to states, eliminate the law’s mandate that requires all Americans to have insurance coverage or face a penalty and carve out deep cuts to Medicaid, the national insurance program for low-income families.



Under the plan, millions of Americans could lose insurance coverage as spending discretion is transferred to the states in the form of block grants calculated according to a complex formula that accounts for factors such as cost of living and population density. The proposal would also allow states to waive ACA protections that prohibit insurers from charging higher premiums to sick people and ensure that healthcare plans include benefits such as maternity care and mental healthcare.

Race before 30 September deadline

If the Senate passes the measure, the bill then goes to the House, where Graham said he had assurances from the House speaker, Paul Ryan, that it would pass. The House could not change the bill after the 30 September deadline without returning it to the Senate, where the bill would then require 60 votes.



In an effort to rally support, some Republicans have argued that the Republican healthcare plan is the only way to prevent Democrats from enacting universal healthcare, a virtual impossibility with a Republican-controlled Congress.

During a press conference on Tuesday, Graham held up his hands for emphasis: “Federalism or socialism,” he said.

On the same day last week that Republicans introduced their healthcare plan, Senator Bernie Sanders of Vermont, an independent, unveiled his “Medicare for All” bill, which would establish a government-run health insurance program and guarantee coverage for all Americans.

While the Vermont senator has stated clearly that the legislation will not pass in a Republican-controlled Congress, the universal healthcare plan has served a useful foil for Republicans. Speaking to reporters aboard Air Force Two earlier on Tuesday, Graham said Sanders’ bill was a “gift from God”.

Chuck Schumer, the Senate minority leader, said Democrats remained uniformly opposed to the Republican plan, which he called “a sham” and the “most dangerous” repeal legislation yet.



Senator Elizabeth Warren, who supports Bernie Sanders’ universal Medicaid proposal, called the Republican plan ‘cruel, heartless, shameless’. Photograph: Yuri Gripas/Reuters

Democrats have declared this a “red siren” moment and are running a full-court press to draw attention to the legislation. On Monday night, Senate Democrats staged an hours-long talk-a-thon in protest. Elizabeth Warren, of Massachusetts, slammed the bill as “another version of the same old cruel, heartless, shameless plan that Republicans have spent the last eight months trying to jam down the throats of the American people” and Senator Chris Murphy of Connecticut called the proposal the “meanest version of Trumpcare yet”.



In recent days, Donald Trump and Pence, along with other administration officials, have worked the phones to pressure senators, including Joe Manchin, a Democrat from West Virginia who is not expected to support the bill.



But complicating the outreach, a group of 10 governors – including five Republicans – came out against the measure, urging senators to abandon the plan and pursue a bipartisan path. Influential health care groups including AARP and the American Hospital Association have also announced their opposition.

If Republicans can cajole 50 of their 52 members to support the bill before the end of the month, they will vote without knowing the impact on insurance coverage or premiums. The Congressional Budget Office said it would release a “preliminary assessment” by next week, but would not have an full analysis for “at least several weeks”.

Republicans can only afford to lose two votes if Democrats remain uniformly opposed to the bill. Already Senator Rand Paul, a libertarian from Kentucky who favors wholesale repeal, has said he was firmly against the Graham-Cassidy legislation because the plan retained too much of the ACA framework.

A trio of Republican senators who felled the last effort to repeal the ACA in July remain publicly undecided. Senator Susan Collins of Maine said she had a “number of concerns” with the legislation, especially the deep cuts to Medicaid . Senator Lisa Murkowski, of Alaska, said she has not made up her mind and is in close contact with the state’s governor, Bill Walker, an independent who on Tuesday warned that the plan could exact “drastic cuts” to Medicaid.

Meanwhile, Senator John McCain has expressed concerns with the fast-track process being used to bring the bill to the floor. But he has suggested he may ultimately support the plan.

Graham said senators faced a clear choice. “If you’re a Republican and you vote against federalism, you’ve got to explain to people back home why Washington knows better,” he said, suggesting the proposal could even tempt Democrats.

“At the end of the day, I really believe that we’re going to get 50 Republican votes and I’ll make a prediction: there are going to be a lot of Democrats struggling with a no vote,” he said.