WASHINGTON — For John McCain, everything goes back to a book he picked up in his father's study nearly 60 years ago.

Before his 2000 presidential run made the Arizona Republican senator a political phenomenon. Before his campaign-finance crusade cemented his reformer bona fides. Before the Keating Five scandal nearly cost him what he holds most dear — his reputation. Before the now-legendary U.S. Navy career and its brutal years in a North Vietnamese prison.

Helping guide McCain through it all was a novel: Ernest Hemingway's "For Whom the Bell Tolls," and its protagonist, Robert Jordan, who dies serving a noble but doomed cause in the Spanish Civil War. It was devoured by a precocious 13-year-old who was searching for a way to reconcile his emerging iconoclasm with the rigors of the naval career that his Navy family expected of him.

Young McCain finished the book "aspiring to Jordan's courage and nobility and certain I would possess it someday," McCain wrote in his 2002 memoir "Worth the Fighting For," a title taken from a line in the novel.

"My No. 1 hero of all time!" McCain reiterated earlier this year. "I am an incurable idealist and romantic. Robert Jordan is everything I ever wanted to be. I read that book at age 13 and now at age 70. Nothing's changed."

Nothing's changed, but much has transpired. More than any other candidate for president in 2008, McCain has publicly unwrapped and examined his life in interviews, speeches and memoirs, all the while gauging whether he's met the standard that his fictional hero set.

"I think it's important to McCain that he believes what he's doing is right," said Mark Salter, McCain's longtime aide and writing partner. "It's more important than success, which is important — he's an ambitious guy. But he has to believe he's acting honorably."

Frequently he's succeeded, most famously in his heroic survival of 5 1/2 years as a prisoner of war in North Vietnam, the searing, defining drama of his life. Recently discovered video footage of that time is now being broadcast in McCain television ads in New Hampshire.

"He was one of the tough guys," said Paul Galanti, a fellow POW who's supported both of McCain's presidential bids. The North Vietnamese "really hated him. ... Among his peers, he was just a born leader."

FOLLOWING HIS HEART

In Congress, he followed his heart — if not political expediency — by opposing the deployment of Marines to Beirut in 1982, defying the wishes of President Reagan and his Republican elders, and supporting U.S. force in the Balkans in 1995, against the wishes of most Republicans, including Texas Sen. Phil Gramm, whose presidential campaign McCain then chaired.

At other times, McCain has faltered. There have been private failures, such as the breakup of his first marriage. And public ones: McCain's involvement in meeting with federal savings and loan regulators in 1987 on behalf of a banker who later was revealed to be corrupt tarred the Arizona senator as one of the "Keating Five." That led to a lengthy Senate ethics inquiry, which ultimately absolved McCain of misconduct.

McCain called it "one of the worst experiences of my life." He feared for years that he'd earned a reputation as "a man whose favor could be bought."

Redemption came via reform, as McCain worked to sever the relationship between campaign fundraising and governing. After years of effort against the vigorous opposition of much of his own party and deep-pocketed special interests, the McCain-Feingold campaign finance reform bill became law in 2002.

It all led to a rollicking, but failed, 2000 presidential bid in which McCain revealed his full self to an unsuspecting electorate: funny, engaging and relentlessly — indeed, almost pathologically — honest. Until he wasn't — when he tried to finesse whether the Confederate Stars and Bars should fly over the South Carolina state capitol. He pleased no one, including himself.

McCain's 2000 presidential dreams died in Dixie, the flag issue just one of many that derailed him — including a vicious whispering campaign that suggested that he was deranged and the father of an illegitimate black child. McCain later wrote that he'd been "dishonest" and "a coward" about the flag, a tough confession for a Hemingway acolyte.

As if to fix the wrong he'd committed against himself, McCain returned to South Carolina after his campaign collapsed to give a speech saying he opposed flying the Confederate flag.

AMBITION VS. IDEALISM

McCain started the 2008 campaign a favorite for the Republican nomination. Yet he's faded in polls and fundraising, victimized in many ways by his penchant for independent thinking, his determination to live as he thought Jordan would: "All the attributes of happiness do not make a life well-lived if we are afraid to risk it all for the love of something finer, something bigger than our own desires," McCain wrote.

So his desire for the presidency occasionally collides with his work for what he considers something finer.

First, there are his apostasies from Republican dogma. To campaign-finance reform and the distrust of his party's religious wing, some of whose leaders he's gone out of his way to alienate, add the tinderbox issue of immigration. His support for a comprehensive immigration overhaul, rather than the conservatives' preferred enforcement-only approach, has earned him the nickname "Juan McCain" from the talk-radio right.

Then there's what McCain's admirers on the center and left consider his inexplicable embrace of an unpopular Iraq war. While most Republican voters remain supportive of the war, independents and the national media have turned against it, and it was they who were most thrilled by McCain's campaign in 2000. McCain was mercilessly mocked last spring when he deemed a Baghdad marketplace safe while he was guarded by hundreds of U.S. troops.

Yet to understand McCain, "the incurable idealist and romantic," is to realize that he asks for redemption only when he's failed to meet his own standards, not those of others. He considers the Iraq war not simply the defining issue of the campaign, but of a generation; believes himself the best prepared by dint of experience and temperament to lead what he considers a necessary fight; and hopes that Republican voters will favor a man of steady conviction over the likes of Mitt Romney and Fred Thompson, whom he considers chameleons and latecomers.