Of the eight decades he spent on earth, fully six of them were dedicated to public service. That legacy of service is something the likes of which we may not see again. The passing of McCain provides the American body politic a moment to pause and reflect on the remarkable life of the Arizona Republican.

McCain has been part of collective national consciousness for the better part of the last five decades -- ever since his capture and ultimate release five years later (in March 1973) from a Vietnamese prisoner of war camp . The stories of his torture at the hands of the Vietnamese were -- and are -- excruciating. His unwillingness to use his status -- his father was an admiral in the Navy -- to gain early release from the camp exemplifies a selflessness and sacrifice most of us can't even begin to imagine.

Less than a decade after he emerged gaunt and hobbled from that prison camp, McCain was in the US House. Four years after that -- in 1986 -- McCain was elected to the seat left behind by the retirement of Sen. Barry Goldwater.

Rising star

His rapid rise in politics was slowed during the early 1990s when McCain was implicated in the " Keating 5 " scandal in which he and four other senators were accused of exerting their influence on behalf of a wealthy campaign donor named Charles Keating. The Senate ethics committee ultimately found that McCain "exercised poor judgment in intervening with the regulators' on Keating's behalf" but added that the actions he undertook "were not improper nor attended with gross negligence."

Slowly but surely, McCain began to build a national profile in the wake of that scandal -- and heavily influenced by it. Having flown too close to the line between money and politics, McCain was reborn as a committed reformer, with campaign finance reform as his main priority.

Even so, McCain was largely ignored as a major player in the 2000 presidential race when he announced his candidacy in September 1999 . Then-Texas Gov. George W. Bush was considered the all-but-certain nominee and McCain wasn't seen as one of the people who might even have a puncher's chance against the scion of the first family of Republican politics.

Presidential run

But McCain caught lightning in a bottle in a way that can only happen in the swirl of a presidential primary campaign. Riding around New Hampshire in a bus dubbed the "Straight Talk Express," McCain became the ringmaster of a compelling political circus -- holding court for hours on end with reporters and aides about whatever topic anyone could think of.

It was a political campaign the likes of which seemed to only ever exist in the movies; an exuberant, upstart campaign that played free and loose because the candidate knew he had nothing to lose.

When McCain crushed Bush by 18 points in New Hampshire, he looked and sounded every bit the giant killer -- the maverick who had beaten the Man. Reality hit back hard in the South Carolina primary, which is still seen as one of the nastiest races ever conducted. McCain's loss to Bush there effectively ended his insurgent bid and left him deeply embittered toward Bush and the Republican Party that had rallied against him.

Republican Presidential nomination hopefuls (L-R) George W. Bush, Gary Bauer, and John McCain debate in January 2000.

McCain found a silver lining -- as he always seems to do -- using his newfound national profile to push through comprehensive campaign finance reform -- against the wishes of almost everyone in his party -- in 2002.

By 2004, McCain had shelved the enmity between he and President Bush and campaigned hard for the president's re-election against then Sen. John Kerry -- a move that won over many rank-and-file Republicans who had been leery of McCain's outspoken outsider campaign. When the country started to turn on the Iraq War, McCain encouraged Bush to surge troops back in -- a key decision for his formal rival and the nation.

McCain is unique in politics as someone who will speak his mind and support his conscience. He ran for president in 2008 and started as the front-runner. But, hamstrung by his prominent support for comprehensive immigration reform -- something wildly unpopular to much of the GOP base -- McCain's campaign totally collapsed in the summer of 2007

Lots of politicians -- heck, most of them -- would have given up. McCain just kept getting on those southwest flights to Manchester, New Hampshire. Relentlessly, he began to, again, build himself back up in the state that had launched his first presidential campaign. New Hampshire again went for McCain -- and this time he used it as a springboard to catapult himself to the nomination.

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It was a nomination that turned out to be barely worth having. The unpopularity of Bush, the Wall Street collapse and the once-in-a-generation political talent of Barack Obama ensured that the 2008 general election was never really close. (McCain didn't help himself when, in the midst of the financial panic, he declared that "the fundamentals of the economy are strong."

That convincing defeat ended McCain's chances of being president. But it began this most recent phase of his life -- as a statesman.

"I remind all my colleagues: We had an election," McCain said when he returned to the Senate in January 2009 . "I think the message the American people are sending us now is they want us to work together, and get to work."

In the intervening years, McCain cemented his role as a hawkish voice on foreign policy, a fierce defender of the military and, yes, someone who occasionally -- and with glee -- throws a wrench into the machinations of his own party. Following the election of Donald Trump in 2016, McCain has repeatedly blasted the Republican president for his handling of Russia and its efforts to meddle in the election as well as for Trump's firing of former FBI Director James Comey.

I love @SenJohnMcCain. Unbeatable, unbreakable. He's Teddy Roosevelt's "man in the arena" even when we're on opposite sides. God bless. pic.twitter.com/0sBY4QynWp — John Kerry (@JohnKerry) July 20, 2017

The regard with which McCain is held within the Senate -- and politics more generally -- was reflected in the encomiums offered to him. Mitch McConnell and Joe Biden praised him. So did Ted Cruz and Nancy Pelosi.

Kerry, his former rival, used the Teddy Roosevelt quote, "a man in the arena," to describe McCain. It's one of the Arizonan's favorites. He used it for one of his best TV ads of the 2000 campaign.

McCain, as he was the first to tell anyone who asks, was not a perfect politician. He sacrificed principle in favor of politics at times. He said things in the heat of the moment he regretted later. His story is not "Mr. Smith Goes to Washington." He is someone who sacrificed much for the country and to whom the country has given much in return.

His story is truly amazing not because he did everything right or because everything went his way. He didn't. And it didn't. His story is amazing because his life isn't about a steady ascent to the top. It is about a series of falls, missteps and hurdles -- none of which he allowed to beat him.

McCain isn't a man who was never knocked down. He's a man who just kept getting up.