Update at 4:05 p.m. ET
Sen. John McCain, diagnosed with a deadly form of brain cancer just five days ago, returned to applause on the Senate floor Tuesday, where he cast a crucial vote to move forward on repeal of the Affordable Care Act and urged his colleagues to regain their sense of bipartisan cooperation.
However, the longtime Arizona senator, two-time presidential candidate and perhaps America's most famous former prisoner of war, warned that he "will not vote for this bill as it is today," describing it as "a shell."
McCain said he would attend the Senate for a few days and then go home to Arizona to recuperate.
"I have every intention of returning here to give you all reason to regret the nice things you said about me," he told his fellow senators, addressing the outpouring of support he's received since announcing his diagnosis.
It was a remarkable moment, to see McCain, whose daughter described him poetically as a "warrior at dusk," take his place again in the "world's greatest deliberative body," where he has represented his southwestern state for 30 years.
McCain, with surgical stitches clearly visible above his left eye, admonished both Republicans and Democrats to work together in the old way and to stop trying to make laws "behind closed doors."
He acknowledged that it was easy to fall victim to the urge to win instead of doing what is right. "Merely preventing your political opponents from getting what they want isn't very inspiring," he said.
And, he advised strongly: "Stop listening to the bombastic loudmouths on the television, radio and Internet. The hell with them!"
Meanwhile, McCain's vote, along with a tiebreaker from Vice President Mike Pence, gave Republicans the 51 votes they needed for the "motion to proceed."
A motion to proceed is what it sounds like — a measure to allow debate to begin. There will be 20 hours of debate, which will expire Wednesday, NPR's Susan Davis reports.
Republicans could only lose two votes for a majority without any Democratic support. Sens. Susan Collins, R-Maine, and Lisa Murkowski, R-Alaska, both voted no.
Beyond the motion-to-proceed vote and the ensuing debate, no one is quite sure — not even Republicans — what of substance the GOP will try to pass to overhaul health care, which affects roughly one-sixth of the U.S. economy.
Senate Majority Leader Mitch McConnell, of Kentucky, promised to bring a full repeal of the Affordable Care Act with a two-year delay to the floor, which President Trump seemed to be on board with. But, up to this point, the votes aren't there for that approach; too many Republicans have come out publicly opposing the idea.
So then what? If the full repeal isn't brought to the floor, or if it fails, then it's on to the Senate's version of no-holds barred — a "vote-o-rama," where anyone can bring any amendment to the floor and have it voted on.
That would be kind of like doing the work normally done for months in committees out on the Senate floor in a matter of hours and days.
This is just the latest chapter in Republicans' difficulty replacing the ACA, also known as Obamacare. Legislatively, they have been plagued by starts and stops during the Trump presidency, unable to get their differing ideological factions on the same page.
"Obamacare is the law of the land," House Speaker Paul Ryan, R-Wis., declared after the House's health care flameout months ago.
But, through arm twisting and legislative tweaks, the House eventually passed a version that tinkered with the ACA. The Congressional Budget Office said the law would increase the number of uninsured by tens of millions, especially because of how it would change Medicaid.
Nonetheless it was a political victory, if only a lead at halftime. It was greeted by Bud Lights in the House and a Rose Garden celebration with the president of the United States. There was no "45" jersey with GOP on the front and "Trump" on the back, but there might as well have been.
One would have thought a new law had been signed. It hadn't. The House version was headed to the Senate, where it would certainly change and have to be reconciled with the House.
Back to the drawing board.
Nearly three months later, that Rose Garden ceremony remains the high point for Republicans. The GOP has not been able to gather the votes in the Senate — and that has started to really rankle Trump. His irritation was evident during his appearance Monday at the Boy Scouts National Jamboree in West Virginia.
"As the Scout law says, a Scout is trustworthy, loyal," Trump said. He added, "We could use some more loyalty, I will tell you that."
Speaking of Health and Human Services Secretary Tom Price, who was on stage with him, Trump said, "Hopefully he's going to get the votes tomorrow to start our path toward killing this horrible thing known as Obamacare that's really hurting us."
Trump spoke of Price as if he were McConnell, as if he had some control over whipping the votes on health care. Price wasn't even a senator before joining Trump's Cabinet; he was a member of the House from Georgia.
He went on: "By the way, are you going to get the votes? He better get them. He better get them. Oh, he better. Otherwise, I'll say, 'Tom, you're fired.' I'll get somebody."
Then Trump turned to Price, smiling, as if to say, "Only kidding."
Or maybe not. That came on the same day he called his attorney general, Jeff Sessions, "beleaguered."
On Tuesday morning, he tweeted criticism of Sessions, calling him "weak" on Hillary Clinton and "leakers" from the intelligence community.
Speaking to the Scouts, Trump wasn't quite done yet: "He better get Sen. [Shelley Moore] Capito to vote for it. He better get the other senators to vote for it. It's time."
At that time, Capito, a West Virginia Republican, was one of the holdouts on voting for what Republicans have so far proposed when it comes to health care. She was one of a dozen or so senators who had not committed to even voting for the motion to proceed. (During Tuesday's vote, she did support the motion.)
The Boy Scouts is supposed to be an apolitical organization, and after the speech, the group put out a statement saying it does not endorse any candidate.
Trump has begun referring to Republicans as "they" and "you" ("they" promised to repeal and replace Obamacare for seven years; "you" didn't do it). It's a remarkable effort to separate himself from the party he is supposed to lead.
He tweeted that any senator who votes against the motion to proceed is for Obamacare.
And he seemed to threaten them politically.
Where any of this goes is anyone's guess. But as a nation watches a new president who is blowing through with Twitter maelstroms and appears ready to politically fire in all directions, the Senate paused for a few moments Tuesday to recognize a man in McCain who means something very different.
And then it was back to the wind — with Trump, speaking immediately after McCain's remarks on the Senate floor, about how no Democrats had voted in favor the Republican effort to undo Obamacare and reaffirming his recent negative comments about Sessions.