Bush left Austin last Saturday on a plane he christened Great Expectations. As the MD-80 rumbled down the runway, he came on the intercom. “Please stow your expectations securely in the overhead bin,” he said. “They could fall and hurt someone.” But two hours later in Iowa, it was clear that the Bushies had left nothing to chance. Advance work is in their blood. Bush was greeted in an echoing hangar at the Cedar Rapids airport by hundreds of well-wishers, and as he strode to the rope line, they gave out a thunderous cheer on cue. Then it was on to Amana, where Bush stood on a dais of hay bales and vowed to campaign flat out. “I’m running and I’m running hard,” he said. “I’m taking my front-porch campaign to every front porch in this state. Face to face. And I cannot wait.”

It looked like a coronation in a cornfield. But “W” is the sobered son of a candidate who suffered one of the most unlikely defeats in modern political history–and who understands polls are fickle. “[George W.]… knows that I was at 91 percent one day and ended up trying to keep my snorkel above 30,” the former president told NEWSWEEK in an interview last week. “He remembers and he won’t get cocky or read too much into [the numbers].” Though the governor’s aides made fun of the expectations game last weekend, handing out a “How Did He Do?” scorecard to reporters on the plane, they also understand it can’t be as easy as it seemed on a sunny Saturday in Iowa. “I take nothing for granted,” the governor said, and the election-night vote “is the only poll that counts.”

So it has begun again, in Iowa again, with a Bush again. Two decades after George Herbert Walker Bush crisscrossed the state in his first presidential campaign, his eldest son was taking the first strides along the identical path. But other than the itinerary and the family name, little about the odysseys–or the candidates–is the same. Bush the Elder was a driven early achiever–war hero at 20, husband and parent at 22, millionaire at 40–who friends assumed would one day become president. By June 1979, he was a veteran politico who’d run six races in Texas, been chairman of the Republican Party and served in three cabinet-level posts. He was, even so, a long shot: a party pol with nothing to lose.

His son is something else entirely, a poster child for late-blooming baby boomers. George W. once was the winsome life of the party who liked a good time, flew combat jets stateside (not in combat) and had no career path to speak of until well past 40. Few people–even in his family–saw him as a future political superstar. W was just a baseball executive with a famous name when he won the governorship of Texas five years ago at the age of 48. Now he’s a full-fledged phenom, a rookie leading the league in potential. He’s the popular two-term governor of the nation’s second largest state, a champion of that house blend of ideology he calls “compassionate conservatism” and a missionary to the Hispanic and female voters the GOP needs. He is the front runner for president–with nowhere to go but down.

To stay aloft, Bush must deploy the best of his family’s advantages–the money, contacts and tradition–with his own best selling points, which include his charm, his record in Texas and a family name that remains popular in Republican circles. He has to avoid his father’s mistakes, chief among them a penchant for seeming to rock in the crosswinds of his own party. He must demonstrate that he’s his own man–not just his father’s son. And he’ll have to show that he and his largely homegrown team of Texas Political Rangers are ready for prime time.

It’s clear that the son has articulated to himself the lessons of his father’s defeat eight years ago: Promise only what you can deliver. Run scared, always. Avoid bureaucratic lethargy by keeping your own inner circle small. It’s OK to employ credentialed establishment types, but put the good ole boys (and girls) in charge. Think of campaigning and governing as two sides of the same coin. Save up political capital, but don’t be afraid to spend it: that’s what it’s for. Have a clear “vision” to explain to voters–and tell them your bedrock principles every day. So far, Bush the Younger has followed them all. But that’s in Austin. Now he has to do so in Iowa, New Hampshire and the rest of the country.

The early signs–and they are indeed early–are good. In the new NEWSWEEK survey, Bush nearly laps the Republican field, leading the second-place candidate, Elizabeth Dole, by a 47-16 percent margin. He continues to clobber both Vice President Al Gore (54-38 percent) and former senator Bill Bradley (57-33 percent) in test match-ups. More important, Republican voters who are supporting him do so primarily for what Bush and his handlers would regard as the right reasons. GOP voters think he can unify the party and country (27 percent) or because they think he has done a good job as governor of Texas.

But there is a caution in reading numbers, too. As ornery as Texas can be, former president Bush said last week, his son has been playing “Triple A ball.” Running for the presidency is “the major leagues,” where the competition will be “bigger, tougher, stronger.” His son acknowledges that he’s had an easy ride so far. “Look, these polls are going to change, I know that,” the governor says. “I know what’s coming.”

But do the voters? While Bush was a model of specificity in his Texas campaigns, he has yet to say much about his agenda for president. In his first major campaign speech he promised to cut taxes, support private accounts for Social Security and “a touch of iron” in foreign policy. He wasn’t above telling Iowa locals exactly what they wanted to hear–that he’d compete in this summer’s straw poll in Ames; that he supported government subsidies for ethanol, a fuel made from corn (anathema to his home state of Texas). But it’s mostly mood music for now. In the NEWSWEEK Poll, only 5 percent of GOP voters say they know “a lot” about Bush, and just 28 percent say they know “some.” Democrats scoff at the governor’s insistence that he will offer the specifics of his agenda when the country is paying closer attention. “I’d call a hundred reporters on his campaign plane ‘close attention’,” said Paul Begala, the tart-tongued political consultant who advised Bill Clinton in two national campaigns. “Bush has got it bass-ackwards. You have to say what you want to do first, and then go out and sell that to the country. To say ‘I’ll do it later’ is an insult–and is going to lead him straight to disaster.”

That may be wishful thinking, but Bush’s first attempt last week to be specific about national policy–on the all-important issue of taxes–did cause a minor stumble at the start of his campaign. Last fall, Bush’s aides told leaders of a national antitax group that their boss would promise–when he began his campaign–not to “raise net income taxes” if he were elected president. But when asked recently by a New Hampshire reporter about signing such a “pledge,” one of Bush’s aides in Austin declared that the governor never signs such documents.

News that the son of “read my lips” seemed to be waffling on the “pledge” was a big story in New Hampshire, ground zero of antitax sentiment. The next day Bush’s aides hurriedly arranged for him to write a letter in which he committed to the wording of the pledge. But unlike all the other GOP candidates, Bush didn’t sign the piece of paper sent to him by the group, Americans for Tax Justice. “We were going to send that letter all along,” a top Bush aide said. “Too bad we didn’t do it a day earlier.” Bush had fouled off the first pitch he faced in “the Show.” And the insistence on putting his promise in his own words seemed decidedly Clintonian.

From now on, every move and every stumble will draw the same kind of microscopic scrutiny, all aimed at answering the question “Who is George W. Bush?” Voters may think they’re about to get a Louis Auchincloss sequel, the next installment in the Yalies’ dynastic urge to preserve their prerogatives. But W is a more complex character than that, a salsa of traits derived from his strong-willed mother, his attentive wife and his roots in west Texas. The lurking temper and tart smile–and tart remarks–come from his mom, Barbara Pierce Bush. (He also inherited a list of contacts and financial supporters that traces its origins to his mother’s Christmas-card list. And she’s still at it: one of the first mass fund-raising letters that the governor sent this year went out over her signature.) The earnest, Bible-study Methodism comes from his wife, Laura Welch Bush. The twang in his voice and the silver buckle on his jeans come from a childhood spent on the ball fields and in the public schools of a town in the oilfields. “Ask me where I’m from, and I have the answer,” he once said. “Midland, Texas.”

Both father and son are friendly sorts, but in different ways. The former president is the kind of frenetically sociable fellow who invited stray politicians home for supper in Washington without bothering to warn his wife–or so the family lore has it. But he is a rather shy and reticent Yankee for all that, more comfortable writing notes (or sending e-mail) than slapping backs. He keeps a certain distance. He won’t pick a fight for fun, or just to get a reaction. As for holding grudges, he has a long memory but an essentially forgiving nature.

W, by contrast, is his mother’s son, and a shoot-from-the-hip Texan by upbringing. He can’t wait to launch the next zinger. He’ll put you in a mock hammerlock as a testament to combative friendship–combat and friendship being more or less the same thing in his locker room of life. He loves handshakes, secret and otherwise, and will demonstrate them without being asked. There is a method in these abrazos. He is poking to get a response, and to answer the essential question: are you with me or not?

And if you’re not, you never will be. W never forgets a slight, and has a lifelong catalog of them in his mind. His mental files are based on the kind of sharp judgments he makes of everyone he meets. “If he studied much in college I didn’t see it,” said Lanny Davis, a former Clinton White House aide who was a Yale friend of Bush’s. “What he did study was people. George had a take on everybody. We’d sit in the lounge and he’d comment on everyone who passed by. He was usually dead-on.”

To outsiders, the Bushes seem to embody a kind of permanent WASP culture, as immutable as the rocks at Walker’s Point, the family’s century-old retreat on the coast of Maine. But in fact they have always been on the move, blazing a trail farther and farther away from their midcentury status as quintessential Connecticut Yankees. Prescott Bush wore a raccoon coat on the stage of Woolsey Hall at Yale in 1952, introducing his friend Dwight Eisenhower to New Haven. He and his wife, Dorothy, were devout Episcopalians, reading the Bible every morning at breakfast. His son George moved to Midland, and taught Sunday school, but at the Presbyterian church. And his son George W. taught Sunday school in Midland, too, a generation later. But it was at the Methodist church, where his wife, Laura, was a mainstay–and where the prayers were more fervent and open than Eastern Episcopalians would have been comfortable with.

W himself traveled for his schooling, going back East for Andover and Yale. But he still thinks of Sam Houston Elementary and San Jacinto Junior High as his educational lodestars; Laura’s experience teaching in the Midland public schools reinforces that view. His own 17-year-old twin daughters, Jenna and Barbara, attend Austin High.

The Bushes have also had a nose for the next opportunity. W’s great-grandfather made a fortune in railroad manufacturing; his son Prescott was a pillar of old Wall Street finance. Like his grandfather and father, W leavens his prep-school heritage with a love of sports. After a lackluster business career, W finally hit it big when he was brought in as a partner in the purchase of the Texas Rangers baseball team. His original $606,302 investment–most of it borrowed from a bank where he was once a director–netted him a fortune of $18.4 million, and accusations that he had benefited from a sweetheart deal. Bush answers that his salesmanship and contacts were crucial to the deal’s success.

Bush also inherits the history of a family that has been at or near the pinnacle of national politics for decades. His great-grandfather was active in Ohio politics; grandfather Prescott was elected twice to the U.S. Senate from Connecticut, serving from 1952 through 1962. Besides W, the current generation features another potential national figure: his younger brother Jeb, the popular Republican governor of Florida.

The notion that W is a rank novice who wandered onto the national stage is misleading. As a youth he was ambivalent about the family business–politics–but he absorbed its ways. When his father ran for the Senate in Texas in 1964, the year Barry Goldwater headed the national ticket, “Georgie” took a copy of “Conscience of a Conservative” with him to prep school. When Dad ran for Congress two years later, his eldest son chalked up vote tallies. The son ran for Congress in 1978, and acquitted himself well in a close race in west Texas. He played a key role in his dad’s 1988 campaign, acting as the family consigliere and learning the arts of war from the late Republican strategist Lee Atwater.

His father’s loss to Bill Clinton galvanized the son. But to win the White House for himself, Bush must address another piece of family history. For generations, the Bushes have been troubled by–and had trouble with–the GOP right. His grandfather was a consummate Ike man, flummoxed by McCarthy and the Red-baiters. His father never bonded with the New Right activists who despised him even after he became leader of the party the Gipper built. If W can get the right wing to ease off–or roll them in the primaries–he can call the party of Ike and Reagan his.

He has a head start in Texas. The Lone Star State is now the national anchor of the GOP, and a demographic preview of America in the 21st century. Buoyed by dramatic economic growth in high tech and real estate, the Texas economy has produced a huge flood of tax revenue. That, in turn, has made it easier for the governor to pursue his “compassionate conservative” agenda, cutting $4 billion in taxes and raising spending on education at the same time. The same kind of math won’t necessarily work in Washington.

But in Iowa, on the campaign’s opening day, the fine print didn’t seem to matter. In Cedar Rapids and Amana, in downtown Des Moines and out at the Fairgrounds, the crowds were large, the speeches well crafted and the voters genuinely eager to meet the man and listen to his carefully balanced message of heart and mind. He seemed happy to have plunged in. He was “focused”–a favorite word. Aboard Great Expectations, he went on to Maine, to the old family place in Kennebunkport. When his dad was in office, and in residence, the blue presidential standard flew from a flagpole on the lawn. If the son has his way, the colors may soon fly there again.

Photo: FAMILY MATTERS: The Bushes gather last week at a benefit for the M.D. Anderson Cancer Center Photo: INTO THE ARENA: Bush campaigning in Cedar Rapids, Iowa, last week Photo: THE NEXT LEVEL: A briefing with George Shultz and Condoleezza Rice Photo: THE “W’ ALBUM: With Bush Sr., then a Texas oilman, at an rig- dedication ceremony in 1956 (left), and as a cheerleader at Andover in 1964 (top right). Lieutenant Bush of the Texas Air National Guard (middle right) and George W. the family man in 1997. He and his wife, Laura, flank their twin daughters, Barbara and Jenna