WASHINGTON — Despite his sharp criticisms of nearly every health-care bill pushed by Republican leadership this year, Ohio Sen. Rob Portman sided with party leaders Tuesday to keep alive the GOP effort to dismantle and replace Obamacare.

By joining 49 other Republicans and Vice President Mike Pence, the Ohioan cleared the way for the Senate to launch a floor debate and provide lawmakers with an opportunity to amend a bill Republicans have promised for years.

Portman’s vote could be among the most divisive of his seven years in the U.S. Senate. Although conservatives are demanding a repeal of Obamacare, polls show a strong majority of Americans oppose the Republican efforts.

That Portman — who has consistently expressed concern about the repeal’s effects on the Medicaid population, especially those receiving opioid treatment — decided to stick with his leadership should be relatively unsurprising: The FiveThirtyEight blog says he has voted with President Donald Trump 95.5 percent of the time. But the senator remains noncommittal on whether he will vote to approve whatever bill makes it to a vote.

Senate Republicans won his vote for debate in part by promising to push a Portman amendment to the Senate GOP's most-recent health-care bill that would add $100 billion to help people transitioning from the Medicaid expansion to private insurance.

It was a promise with which Sen. Sherrod Brown, D-Ohio, who opposes the repeal effort, was unimpressed.

“You cut $850 billion and replace it with $100 billion,” Brown said after voting against moving forward. “That hardly takes care of the 200,000 Ohioans getting opioid treatment.”

During a Rose Garden news conference, Trump said, "I believe now we will, over the next week or two, come up with a plan that's going to be really, really wonderful for the American people."

The vote does not guarantee the Senate will approve a bill to scrap Obamacare and pass a substitute for the 2010 Affordable Care Act. Sen. John McCain, R-Ariz., said while he supported the motion “to allow debate to continue,” he insisted he would not “vote for this bill as it stands today.”

McCain, who last week announced he had been diagnosed with brain cancer, provided the most-dramatic moment of the afternoon when he entered the chamber. Senators from both parties stood and applauded, and McCain hugged Senate Majority Leader Mitch McConnell, R-Ky., and Senate Minority Leader Chuck Schumer, D-N.Y.

All but two Republican senators voted to proceed to a full debate: Lisa Murkowski of Alaska and Susan Collins of Maine, who joined 46 Democrats and two independents in voting to kill the effort. Pence broke the tie.

The proceedings were interrupted by a long, restrained protest from the Senate galleries — chants of “Shame, shame, shame” and “Kill the bill” ringing through the chamber.

Portman — who, along with a handful of other senators, has been under intense pressure from both opponents and supporters of repeal — had already called Ohio Gov. John Kasich to inform him of his decision, a source close to Kasich told The Dispatch.

After the vote, Portman said his goal is “to create a more workable health-care system that lowers the cost of coverage and provides access to quality care, while protecting the most vulnerable in our society.”

“I am committed to repealing and replacing this law with better solutions,” he said. “But as Obamacare is replaced, it must be done in a way that gives all Ohioans access to affordable health care.”

Senate GOP leaders added $45 billion during a 10-year span to combat opioid addiction, a move also aimed at winning Portman's vote.

One Republican said the vote “questions the notion that so many in the national media have latched on to — that Rob is some kind of moderate. He’s a conservative with strong conservative principles, but he’s fighting at the same time to ensure the best possible outcome for the state of Ohio.”

McConnell moved forward Tuesday night on a vote on the Senate GOP's plan to dismantle Obamacare as well as Portman’s amendment to add $100 billion for those moving off Medicaid and a proposal by Sen. Ted Cruz, R-Texas, to allow insurers to sell stripped-down, inexpensive plans on the individual markets. But that legislation needed, under Senate rules, 60 votes for passage, and it failed.

That defeat will force Senate Republican leaders to come up with another health-care alternative, possibly a “skinny” repeal — one that GOP leaders hope would include a repeal of a mandate requiring people to buy insurance and the requirement that companies provide insurance. The scrapping of a tax on the production of medical devices also probably would be in the skinny repeal. But the Senate adjourned for the night.

Portman also opposes the version of the bill that the House passed. In fact, he has signaled supreme discomfort with how virtually every GOP repeal bill has rolled back the Medicaid expansion, which has added health-care coverage for more than 700,000 low-income Ohioans.

Kasich expressed dismay Tuesday because GOP leaders never held hearings on a Senate Republican health-care version.

“It doesn’t need to be forced through the floor of the Senate,” Kasich said. “When you have all these amendments, you don’t know what the impact is. We’re talking about health care for Americans. I’ve made myself perfectly clear about what needs to be done about this, but I’m not running the United States Senate.”

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