"Stop listening to the bombastic loud mouths on the radio, television and internet", Mr McCain boomed.
McCain also said he would not vote for the current GOP version of the repeal-and-replace bill.
Senators' work is "more partisan, more tribal more of the time than any other time I remember", McCain told a rapt audience on the Senate floor. "Why don't we try the old way of legislating in the Senate?"
"We've tried to amend the Affordable Care Act by coming up with a proposal behind closed doors in consultation with the administration, then springing it on skeptical members, trying to convince them it's better than nothing, asking us to swallow our doubts and force it past a unified opposition".
"I don't think that's going to work in the end, and it probably shouldn't", he said.
McCain, who has represented Arizona in the Senate for three decades, was the Republican Party's presidential nominee in 2008. Many people that like what I said. McCain planned to deliver a speech on the Senate floor after the vote. He put loyalty to his party, to Republican majority leader Mitch McConnell, and, unbelievably, to President Trump over loyalty to his country and the needs of his fellow citizens. Early Tuesday afternoon, several senators who had previously opposed moving ahead with the health care debate announced they had changed their minds, including Republican Sen.
But in a sign of one complexity they'd face, an upstate New York Republican congressman said he'd oppose the Senate bill if it omits House-passed language granting Medicaid savings to all of his state's counties excluding the five New York City boroughs.
The Arizona senator has emerged as one of Trump's most outspoken GOP critics.
The president's tweet comes just over two years after the then-presidential candidate said McCain, who was imprisoned and tortured during the Vietnam War, was not a war hero because he was captured. And, like Kennedy before him, he received a standing ovation from senators of both parties.
McCain's return was reminiscent of a similar scenario involving McCain's good friend, the late Democratic Sen.
His Senate office said Wednesday that he was in "good spirits" and recovering at home in Arizona with his family. "No", Graham said. "It's surprising he's been in the hospital this long".