"When John saw an issue the same way you did, you knew you’d just found your most stalwart ally. You’d thank your lucky stars. Because when you found yourself on the other side of that table, as I think all of us learned, you were in for a different kind of unforgettable experience," Senate Majority Leader Mitch McConnell said in opening remarks. "Either way, serving alongside John was never a dull affair."
McCain famously sank the GOP effort to repeal the Affordable Care Act last year when he returned from treatment -- a wound still healing above his eye -- to cast a thumbs down vote right in front of McConnell.
"I found myself on both sides of that table over the years," McConnell acknowledged. "John and I stood shoulder to shoulder on some of the most important issues to each of us, and we also disagreed entirely on huge subjects that helped define our careers."
As McConnell spoke, McCain's desk sat draped in black, topped with a vase of white roses.
McConnell reflected on the time he was able to spend with McCain this past May at his home in Sedona, Arizona, where he stayed while he underwent treatment for an aggressive form of brain cancer, glioblastoma multiforme.
"We sat on his back porch in Sedona, under the desert sky, replaying old times," McConnell said.
Senate Minority Leader Chuck Schumer, who began his career in Congress within two years of McCain, also took the floor to commemorate the late senator.
He urged bipartisanship in McCain's honor.
"We can try, as he did, to put country before party. We can try, as he always did, to speak truth to power. And we can try, as he summoned us to try, to restore the Senate to its rightful place in our national political life,” Schumer said about the Republican he'd worked alongside since the early 1980s.
Schumer also called on Republicans to join him in his efforts to rename a Senate office building, currently named for the controversial former Sen. Richard Russell, after McCain. Russell, a Democrat from Georgia who served in Congress for 40 years, was a staunch segregationist.
"It would be a fitting tribute to a man who considers his service here in the Senate, headquartered in the Russell building, where his beloved Armed Services Committee also resides, the most significant of his distinguished career," Schumer said.
The resolution is co-sponsored by Arizona Sen. Jeff Flake, the junior Republican senator who served alongside McCain, Schumer said. Schumer plans to introduce a formal resolution soon.
Flake, who, as McCain was, is often critical of the president, also paid tribute to his mentor and colleague.
"He recognized democracy was hard but living in bondage to tyranny was far harder. Our words are too often cheap and imminently forgettable but John McCain paid our freight with his body and with his soul. To our shame, he lived long enough to have to take to the Senate floor to inveigh against the rank tribalism that we have fallen into lately," Flake said.
The president, who, in comparison to the outpouring of tributes for McCain, has sent only a relatively barren tweet and statement since McCain's passing, was invoked more candidly by Sen. Johnny Isakson, a Republican from Georgia.
"I don't know what's going to be said the next few days about John McCain by whomever ... I don't know what's going to be done," Isakson said.
"But anybody who in any way tarnishes the legacy of John McCain deserves a whippin’," Isakson said in his Georgia drawl. "Cause most of the ones who would do the wrong thing by John McCain didn't have the guts to do the right thing when it was their turn. I would say to the president or anybody in the world, it's time to pause and say this was a great man. He gave everything for us. We owe him nothing less than the respect that he earned," the GOP senator said.
On Wednesday, McCain will lie in state at the Arizona State Capitol. After a private ceremony in the Rotunda there, the doors will open for the public to pay their respects. The public is also encouraged to line the route of the motorcade that will take McCain to a Baptist church in Phoenix for a memorial service, where McCain's children and former Vice President Joe Biden will pay tribute.
On Friday, McCain will lie in state at the U.S. Capitol. On Saturday, a national memorial service will be held at the Washington National Cathedral, where former presidents George W. Bush and Barack Obama will speak. While Vice President Mike Pence is expected to participate in the ceremony at the Capitol on Friday, President Donald Trump will not play a role in any of the events.