WASHINGTON — Senator John McCain of Arizona announced on Friday that he would oppose the latest proposal to repeal the Affordable Care Act, leaving Republican leaders with little hope of succeeding in their last-ditch attempt to dismantle the health law.
Mr. McCain, who killed the previous repeal effort with his dramatic “no” vote in July, released a statement saying that he could not “in good conscience” support the latest proposal, by Senators Bill Cassidy of Louisiana and Lindsey Graham of South Carolina, who is Mr. McCain’s closest friend in the Senate.
“I cannot in good conscience vote for the Graham-Cassidy proposal,” Mr. McCain said. “I believe we could do better working together, Republicans and Democrats, and have not yet really tried. Nor could I support it without knowing how much it will cost, how it will affect insurance premiums, and how many people will be helped or hurt by it.”
With two other Republican senators likely to vote no, Mr. McCain’s opposition to the bill could be fatal, as Senate Republicans could afford to lose no more members.
Senator Rand Paul, Republican of Kentucky, said this week that he would not vote for the bill because it did not dismantle enough of the Affordable Care Act. And Senator Susan Collins, Republican of Maine, has expressed broad concerns about the legislation, strongly suggesting that she, too, would vote against it, just as she voted “no” in July.
Mr. McCain has for months lamented a Senate legislative process that avoided hearings or formal bill-drafting procedures and assumed that an Affordable Care Act repeal bill could clear Congress with no Democratic votes. Those concerns were compounded by the decision of Republican leaders to press forward with a vote next week before the nonpartisan Congressional Budget Office could complete a full analysis of the Graham-Cassidy legislation. The budget office is expected to estimate the cost of the bill early in the week, but could not complete an analysis of its impact on health insurance coverage or premiums by Sept. 30.
That date is critical because Republicans, who hold 52 seats in the Senate, have until the end of this month to make use of special budget rules that would allow them to pass a repeal bill in the Senate with only a simple majority, rather than 60 votes.
“Of course, I’m disappointed,” Senator Cassidy said in an interview, “but that doesn’t mean that I’m going to stop working for those folks who can’t afford their premiums. We are still working. We are still hoping.”
Mr. Cassidy said he had not spoken to Senate Republican leaders, so he did not know what might happen on the Senate floor next week.
But Mr. Cassidy said: “The Affordable Care Act has become too unaffordable for too many people. As long as that’s the case, I’m going to continue working for something that works for that fellow with a daughter who has a pre-existing condition who’s right now paying about $40,000 a year. That’s unaffordable.”
Democrats have vowed that if the legislation could be killed, they would press to resume bipartisan negotiations on legislation to stabilize health care markets under the Affordable Care Act. Republican leaders squelched those talks, led by Senators Lamar Alexander, Republican of Tennessee, and Patty Murray, Democrat of Washington, as they pressed for passage of a full repeal bill.
“John McCain shows the same courage in Congress that he showed when he was a naval aviator. I have assured Senator McCain that as soon as repeal is off the table, we Democrats are intent on resuming the bipartisan process,” said Senator Chuck Schumer of New York, the Democratic leader.
Its death at the hands of Senators McCain, Paul and Collins would be another blow to President Trump, who has tried to pressure Republicans to fall in line.
The Graham-Cassidy bill would take much of the money provided under the Affordable Care Act and send it back to the states, with vast discretion over how to use it for health care or coverage.
The bill has been met in the last few days with a torrent of criticism from consumer groups, doctors, hospitals, insurance companies, governors and state Medicaid officials.
Under the bill, states would have more discretion over how to use federal funds, but most states — including Arizona — would receive less money under the bill than under the Affordable Care Act.
The bill would also give states the ability to opt out of insurance regulations under the health law. States would be able to seek federal waivers that would allow insurers to charge higher premiums to people with pre-existing medical conditions or to omit certain benefits that they are currently required to provide, such as maternity care or mental health care.