(Bloomberg) —Senator John McCain said Friday he’ll vote against the GOP-only Obamacare repeal proposal, becoming the second Republican to oppose the measure and possibly dooming the ability of party leaders to enact it.

“I cannot in good conscience vote for the Graham-Cassidy proposal," McCain said in a statement. "I believe we could do better working together, Republicans and Democrats, and have not yet really tried."

Sen. John McCain
Bloomberg/file photo

McCain joins Kentucky Republican Rand Paul in opposing the bill, while Susan Collins of Maine said Friday she is leaning against it, according to a Portland newspaper. Senate Republicans can afford to lose no more than two members of their 52-48 majority and pass the bill.

The GOP drive to gut the Affordable Care Act is using a dramatically short-circuited process that seeks to replace one landmark health law with another introduced just two weeks ago by Republicans Lindsey Graham and Bill Cassidy. Senate Majority Leader Mitch McConnell has said he intended to hold a vote next week before a Sept. 30 deadline.

President Donald Trump warned on Twitter on Friday, “Rand Paul, or whoever votes against Hcare Bill, will forever (future political campaigns) be known as ‘the Republican who saved ObamaCare.’” The president is working the phone on the issue and is “open to having face-to-face meetings,” adviser Kellyanne Conway said on Fox News. “The president is leaning in all the way.”

The Brookings Institution estimated Friday that the Graham-Cassidy plan would reduce the number of people with health coverage by about 21 million a year from 2020 through 2026. The number may be larger, it said, because of difficulties in setting up state health systems by 2020 and possible market turmoil in the final years. "What is clear, however, is that the legislation would result in very large reductions in insurance coverage," Brookings said.

The Center on Budget and Policy Priorities said Medicaid funding cuts would equal 16 percent of projected state budgets in 2027. "That’s more than what states provide for higher education," it said.

McCain said he would consider supporting a proposal similar to the Graham-Cassidy bill if it were "the product of extensive hearings, debate and amendment. But that has not been the case."

“We should not be content to pass health care legislation on a party-line basis, as Democrats did when they rammed Obamacare through Congress in 2009," McCain said.

Collins criticized the bill because among other things it undermines protection for people with pre-existing medical conditions, according to the Portland Press Herald. "The premiums would be so high they would be unaffordable," she said.

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