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.