Kevin Lamarque / Reuters

In 2000, John McCain’s “Straight Talk Express” barreled down what has become the road not taken for the Republican Party. McCain’s 2000 bid for the GOP presidential nomination is best remembered for his irreverence in the hours he spent happily jousting with reporters on the bus while his campaign strategists abandoned any hope of controlling, much less directing, his message.

But in his insurgent campaign that year against front-runner George W. Bush, McCain also sketched an expansive and inclusive reform-oriented conservatism that harkened back to the early-20th-century vision of Theodore Roosevelt. In the process, McCain advanced a set of priorities and approaches that could still provide inspiration for the small band of Republicans looking to redirect the party from Donald Trump’s divisive and racially infused nationalism—even if McCain himself can no longer lead that fight.

McCain was never a systematic thinker and he would often roll his eyes at rivals who burnished their own agendas with grand labels (like Bill Clinton’s The New Covenant or Bush’s Compassionate Conservatism.) But in the heyday of his maverick period—roughly the decade from the middle of Clinton’s presidency through the second half of Bush’s—McCain created an ideology on the fly, through the causes and commitments he embraced.

During those peak maverick years, McCain venerated above all the notions of duty, loyalty to country that transcended partisan attachments, the cleansing of politics from the influence of special interests, and a pragmatic problem-solving ethos centered on building bipartisan consensus.

These themes powerfully echoed the arguments that Theodore Roosevelt, one of McCain’s heroes, stressed during his own presidency. Often colliding with the conservative “old guard” of the GOP during that era, Roosevelt saw government as a necessary counterweight to the growing power of business and sought to transcend the growing tensions between labor and business, native-born and immigrants, city and country, with resonant appeals to the mutual obligations and shared interests of all Americans. “We are all Americans,” Roosevelt insisted in one speech. “Our common interests are as broad as the continent.”

During the years that bookended the 2000 campaign, McCain embodied those same sentiments. “McCain’s hero is Theodore Roosevelt and they have much in common, a willingness to take maverick stances against Wall Street and big business interests and promoting local communities and the military and civic groups over the shell game of billionaires, outsourcing and the like: Everything about him is really a TR maverick,” historian Douglas Brinkley, who has written extensively about Theodore Roosevelt, told me. “Roosevelt and McCain didn’t believe that the business of America is business; they think of it being about civic duty.”

Roosevelt didn’t always uphold his ideal of a government that transcended “sectional or personal advantage”: He resisted many of the steps that more left-leaning progressives considered necessary to check the power of the expanding corporate behemoths or to promote labor, and at times he bent much too far toward his era’s backlash against large-scale immigration. Neither was McCain immune to the demands of partisan loyalties in an increasingly polarized era: He voted to convict Bill Clinton and remove him from office on both articles of impeachment in 1999. And McCain’s hawkish approach to foreign policy—capped by his unswerving support for the Iraq War—alienated many centrists and liberals drawn to his iconoclastic views on domestic issues.

But during his high maverick years, McCain displayed an unmatched willingness to cross his own party, and to partner with Democrats on tough issues. McCain was never a master of legislative minutiae; details, particularly on domestic policy, bored him. (Among the most futile hours of my life was an attempt to coax him into comparing his approaches to education, entitlement, and health-care reform with Bush’s ideas in an interview during the 2000 campaign.) He operated with the swagger of the fighter pilot he had been, maneuvering more by reflex than reflection. But he recognized, particularly after his meteoric 2000 race, that he had established an unparalleled brand for independence and authenticity that invested great credibility in the causes he cared about. And, over a decade or so of concentrated productivity, he used that credibility to advance a succession of bipartisan achievements.

McCain was the keystone in partnerships with Democrats that led to the passage of the Patient’s Bill of Rights in 2001, campaign-finance legislation (with the Democrat Russ Feingold) in 2002, and, in partnership with Edward M. Kennedy, comprehensive immigration reform (including a pathway to citizenship for the undocumented) that cleared the Senate in 2006. (House Republicans ultimately refused to consider the bill.) He led major bipartisan Senate coalitions that sought to combat teen smoking under Clinton and reduce the carbon emissions linked to global climate change under Bush; conservative resistance eventually blocked both efforts. He helped to broker the 2005 agreement that (temporarily) preserved the filibuster for judicial appointments, while clearing a backlog of stalled GOP nominees.

Even in national security, McCain led the bipartisan effort that in 2005 banned the Bush administration from using torture. And for good measure, McCain voted against both the 2001 and 2003 Bush tax cuts, on the grounds that each was too heavily tilted toward the rich and would open too large a hole in the federal budget. “He is the ultimate reform Republican,” says Brinkley, “but that means he never found a home within the conservative movement, in the same way TR never did.”

During many of these initiatives, McCain’s Democratic partner was Kennedy (who, ironically, died from the same aggressive brain cancer that took McCain.) Both were tough, funny, and thick-skinned: Both believed an opponent today could be an ally tomorrow. And they shared a belief that seems almost quaint now: that the point of the Senate, of Washington, of government, was to find solutions to the country’s big problems. Unlike a growing number of his Republican colleagues, McCain never accepted the contention, immortalized by the anti-tax activist Grover Norquist, that the most important thing government could do was “leave us alone.”

Like Kennedy, McCain was “an institutionalist,” noted Stephanie Cutter, Kennedy’s longtime communications director. “They believed in the Senate. This is an anathema today. Nobody works like this anymore. They were probably the last great partnership.”

The pragmatic, alliance-building McCain was most on display in his 2000 campaign. He began the race as a long shot, far behind Bush, who, as the son of a former president and the governor of the second-largest state, started with massive advantages in money, organization, and name identification. But McCain pounded his message of reform (particularly in campaign finance), duty to country, and non-ideological problem solving through an endless procession of town halls in snowy New Hampshire towns and shocked Bush with a decisive victory in the first-in-the-nation primary there. (I was having lunch on the day of the vote with members of the Bush high command, including the top strategist Karl Rove, who abruptly left the table, ashen faced, as the first exit poll results trickled in.)

With that New Hampshire win, McCain’s “straight talk express” blasted such a hole in Bush’s defenses that the shaken front-runner was forced to rechristen himself as a “Reformer with Results,” in an attempt to take back some of the ground his challenger had seized.

After reinforcing those defenses, Bush mostly ran at McCain from the right in the next critical contest: a scorched-earth South Carolina primary that remains the most riveting political race I have ever covered. Both men inspired massive turnouts over nearly three weeks of gripping campaigning. But Bush ultimately posted a solid victory, setting the template he would follow as he bested McCain through most of the remaining contests: Bush dominated the senator among conservatives, white evangelical Christians, and self-identified partisan Republicans by questioning his commitment to conservative causes (like cutting taxes). Yet even as Bush marched toward the nomination, McCain consistently beat him among moderate and independent voters.

The 2000 campaign model of McCain, like his work in the Senate just before and after that race, presented an ideological hybrid that blended traditional GOP positions on some key issues (such as opposition to abortion and an indivisibly hawkish posture on national security) with the less doctrinaire approaches that allowed him to partner with Democrats in Congress and appeal so heavily to independents in the electorate. “It was an interesting attempt to try to create an anti-D.C., pro-reform coalition on top of a conservative party, by John being strong on defense, right-to-life, and terrific on the [limiting federal] spending stuff,” one of his senior strategists at the time recalled to me last week.

In retrospect, McCain’s 2000 campaign may have represented the last off-ramp for the GOP on the road toward the confrontational and tribal conservatism that has transformed the party over nearly the past two decades. After veering right against McCain, Bush turned back to the center (at least thematically) in the 2000 general election. But in office he governed in a much more partisan manner—even before the Iraq War—and ultimately built his reelection strategy by maximizing turnout among an increasingly militant Republican base (around such issues as banning gay marriage).

By the time McCain ran for president again in 2008, he had grown more isolated in a Republican Party dominated by its most conservative and combative voices. To win the nomination on his second try, McCain was forced to renounce several of his earlier heresies from conservative orthodoxy, particularly his opposition to tax cuts and support for immigration reform. McCain’s vice-presidential choice captured how deeply his impulses were conflicted by that point: When a threatened revolt on the convention floor convinced him to reluctantly abandon his initial idea of running on a unity ticket with Joe Lieberman, the former Democrat then serving as an independent senator from Connecticut, McCain impulsively veered to former Governor Sarah Palin of Alaska, a combative conservative populist who helped to cut the mold for Trump’s later politics of cultural and racial grievance.

All of this positioned McCain as a much more conventional Republican than in 2000, which left him highly vulnerable in the general election to the discontent with Bush, the outgoing Republican president. Yet McCain never entirely surrendered to the rising current of partisan confrontation. When a woman at a town hall questioned the loyalty to America of his opponent Barack Obama (and described him as an “Arab”), McCain forcefully shut her down. Country over party was not just a slogan to him.

With the rise of the Tea Party movement, the GOP further radicalized during Obama’s presidency, shrinking the audience even more for the bipartisan consensus-building McCain had earlier championed. McCain’s own enthusiasm for building bridges also palpably waned with his 2008 opponent in the Oval Office. During Obama’s two terms, McCain functioned more as a conventional conservative Republican than ever before, partly from personal pique, partly because he faced rising conservative resistance at home in Arizona. (Conservatives mounted serious primary challenges against him in both 2010 and 2016.)

Still, even then, he joined the “gang of eight” that again passed comprehensive, bipartisan immigration reform (including a pathway to citizenship) through the Senate in 2013, before the Republican-controlled House once more refused to consider it.

The ascent of Trump, who openly mocked McCain during the 2016 primaries, culminated the Senator’s isolation in the party—but also helped him recover his independent voice. Trump, with his preening self-absorption, open appeals to white racial resentment, and feral attacks on any institution or individual he believes can threaten him, negated all the ideals McCain had espoused at every stage of his career.

Repeatedly, McCain warned of the risks Trump presented to the founding principles not only of the GOP, but the country itself. McCain’s critical vote to block Trump and the vast majority of GOP legislators from repealing the Affordable Care Act on a party-line vote was a powerful statement against the growing sectarianism of modern politics. But now it looks like McCain’s final statement.

Yet even if McCain himself is no longer available to lead the internal Republican resistance to Trump, he bequeaths those critics a usable past. McCain’s 2000 campaign, with its message of reform, duty, and unity that demonstrated a powerful appeal to less-partisan voters, offers the party a potential path to electoral success that does not abandon conservative principles but also does not rely on the divisiveness, vitriol, and racial antagonism integral to Trump’s strategy.

It may be that since 2000, the GOP’s evolution into a party centered on white unease over demographic and social change has advanced too far for a McCain-style message to win a nominating primary. But those hoping to free the Republican Party from Trump’s grip won’t find a better place to start than reclaiming the commitment to service, civility, and civic obligation that defined John McCain’s incredible life.

Editor’s note: The Atlantic senior editor Ronald Brownstein has covered John McCain since his election to the House of Representatives in 1982. His wife served as the communications director in McCain’s Senate office for part of George W. Bush’s second term.

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