"A legend in his own mind," then-Majority Leader Dick Armey, a Texan, acidly called his fellow Republican at the time.
Yet the events of that long day and night in 2002 fit a pattern for a man whose congressional career long has included a singular brand of combative bipartisanship. For more than a decade, on tobacco, health care, immigration, judicial nominees, creation of a commission to investigate the Sept. 11, 2001 terror attacks and more, McCain has championed high-profile legislation opposed by President Bush or others in his own party.
His record of accomplishment is mixed, yet he has made his willingness to cross the political aisle a central theme in his campaign for the White House in an era when voters are plainly tired of partisan gridlock in the nation's capital.
"I believe in bipartisanship, and that's been my record, of reaching across the aisle, whether it be to Joe Lieberman or Russ Feingold, Ted Kennedy" or others, he said recently, referring to Democrats with whom he has worked.
McCain added that he has a "long record of putting my country first, of putting my country not only before my party but before myself. Senator Obama does not have that record."
Sen. , McCain's Democratic rival in the race for the White House, also lists bipartisanship as a congressional credential. A recent Associated Press-Yahoo News poll showed about 40 percent of the electorate believes both men would work across party lines.
Even so, none of the examples cited by Obama's aides, beginning with a bill to secure nuclear weapons in the former Soviet Union, placed the Illinois lawmaker at odds with the leaders of his own party or gave significant offense to outside interest groups aligned with Democrats.
Not so, McCain.
The Arizona Republican "took on his own party's leadership, and that takes enormous courage," says former Rep. Martin Meehan of Massachusetts, a Democrat who worked closely with McCain for years on the campaign finance legislation that Bush reluctantly signed into law. He added that such defiance can often lead to retaliation by the leadership.
"He's a tough adversary. He's a very effective legislator," Senate Republican leader Mitch McConnell said in an interview.
As a longtime member of his party's leadership, McConnell has often borne the brunt of McCain's bipartisanship, yet he said he has never seen him cross an imaginary line into foul territory.
Nor surprisingly, McCain has had triumphs and failures over the years. He's occasionally offended his negotiating partners, and reaped criticism from members of his own party.
Democrats say he can decide quickly what broad concepts he will accept in the give-and-take of negotiations. Republicans say he is too quick to give in to Democratic demands. He is known for speaking bluntly, and for keeping his word.
House Republican leaders were anything but complimentary six years ago, when McCain tried to change federal campaign funding law over their vehement opposition.
When McCain decided on the spur of the moment to work out of an office belonging to then-Democratic Leader Dick Gephardt, they told members of the GOP rank-and-file that it was proof he was doing the Democrats' work.
"He was basically in the war room. It was unusual," said Meehan, who now is chancellor of the University of Massachusetts-Lowell.
At one point, as the measure neared a final Senate showdown, McCain issued a thinly veiled warning to members of his own party. "If I were a Republican up for re-election in the Senate, I'd ask myself, 'Do you want to be part of a continuing filibuster?"' he said at the time.
McCain was the point man in 2005 in the ultimately successful effort to gain Bush's signature on legislation banning the use of torture against detainees in the war on terror.
"We've sent a message to the world that the United States is not like the terrorists," he said at the time, seated in the Oval Office near a president whose aides had once threatened a veto over the ban. McCain's victory came despite a personal, closed-door appeal to Republican senators from Vice President Dick Cheney to exempt CIA employees from the prohibition.
Earlier that same year, McCain was a member of the so-called Gang of 14, a self-appointed group of seven senators from each party that averted a Senate crisis over administration judicial nominees long blocked by Democrats.
The final agreement was sealed around a table in McCain's Senate office.
As a result, some long-stalled appointees were confirmed, angering liberals. Others were blocked, to the anger of conservatives. "I think McCain is going to suffer. He's a great war hero and I think he meant well, but it will be proven to be a mistake," said Chuck Hurley of the conservative Iowa Family Policy Center.
Along the way, two officials said McCain angered another one of the 14, Sen. Joe Lieberman of Connecticut, by bluntly telling him he was taking too long to review the proposed agreement. Lieberman, then a Democrat, walked out of the session in response, according to these officials, who spoke on condition of anonymity. In another episode, Republican Sen. John Cornyn of Texas responded similarly to a tongue-lashing from McCain in a closed-door meeting on immigration in the same year.
Whatever the bruised feelings, McCain and Lieberman work closely on climate control legislation. The Connecticut senator, now an independent, has endorsed McCain in the presidential race because of their mutual support for the war in Iraq.
Not all of McCain's high-profile stabs at bipartisanship have been successful.
After running for president in 2000, he returned to Congress and joined attempts to pass a patient bill of rights. He told Republicans and Democrats alike at the time that in his campaign travels, he had heard numerous times that voters wanted the measure.
Efforts to forge a compromise ultimately broke down when competing outside interests - insurance companies and trial lawyers - could not agree on terms covering lawsuits by patients.
More recently, McCain has been deeply involved in unsuccessful efforts to pass immigration legislation that offers a path to citizenship for millions of men and women in the country illegally. The measure ran aground two years in a row, providing a dramatic illustration of the risks of bipartisanship.
McCain's support for legislation that conservative critics deemed an amnesty bill contributed to the near-collapse of his presidential candidacy. He shifted emphasis - his campaign Web Site makes no mention of his backing for citizenship - and now Democrats accuse him of walking away from an issue he once championed.
Ironically, the campaign season has caused something of a role reversal among Democrats, many of whom once praised McCain for his efforts, and Republicans who formerly struggled to stop them.
Sen. Richard Durbin of Illinois, who was active on legislation to ban torture, declined to be interviewed.
And McConnell volunteered that McCain's views on Iraq, tax cuts and other areas are those of a loyal Republican.
"He has also been with us on a lot of issues too so it's not like he's looking to make a deal on every issue," he said.