"I still have plenty of time to screw this up."

That is Texas Gov. George W. Bush's ironic comment on the Republican presidential race as the shrunken field heads toward a finish line advanced so far in the calendar that Bush says, "This thing is going to be over before a lot of people realize it's begun."

Sitting in his state capitol office, with the shelves filled with autographed baseballs, Bush last week communicated the same sense of bemused disbelief about his apparently rosy prospects that I heard from him a year ago, when we last had a long conversation.

"By this time," said his media adviser, Mark McKinnon, "we thought we'd be in hand-to-hand combat with somebody." Instead, Bush is cruising comfortably ahead of a Republican field that already has shed former vice president Dan Quayle, former Tennessee governor Lamar Alexander, House Budget Committee Chairman John Kasich and Sen. Bob Smith of New Hampshire (now an independent contender) and is about to lose Patrick J. Buchanan, the two-time runner-up, to the Reform Party.

The campaign is entering a new and more testing stage. Many of the others in the GOP field--Sens. John McCain of Arizona and Orrin Hatch of Utah, former Cabinet secretary Elizabeth Dole, publisher Steve Forbes and conservative activists Gary Bauer and Alan Keyes--will participate in a pair of debates in New Hampshire in the next eight days where Bush's absence undoubtedly will be condemned. On Dec. 2 he will expose himself directly to their barbs in another New Hampshire forum.

But barely three months later--on the night of March 7--and perhaps sooner, if no one derails his bandwagon, the contest will be over. Given his support from fellow governors and members of Congress and his huge financial advantage over everyone except millionaire Forbes, "this calendar works fine for me," Bush says--but it's still absurd in his view to pick a candidate months before most voters have begun to focus on the contest.

Bush is intrigued by the proposal to change in 2004 to a rotating system of four regional primaries, held on the first Tuesdays of March, April, May and June--following the traditional leadoff contests in Iowa and New Hampshire. If he becomes the nominee, his potential support for this idea could give legitimacy to some such proposal that a Republican commission headed by former party chairman Bill Brock is expected to bring to the Republican National Convention next August.

Meanwhile, Bush will be completing his round of issues speeches this fall, with statements on foreign policy, the budget and, once again, education. A book (ghostwritten by communications director Karen Hughes) titled "A Charge to Keep" will be published in mid-November, recounting some of the experiences that have shaped his approach to government. Then, in a matter of weeks, the foreshortened voting season will begin.

One advantage Bush sees for himself is that no one opponent appears to be positioned to challenge him everywhere. McCain may be the most formidable rival in the early primaries in New Hampshire and South Carolina, but he is no factor in the January Iowa caucuses, where Forbes and Dole have made major efforts. Bauer barely figures in his calculations, nor does Hatch.

Bush is strikingly cordial toward McCain--a point that should be remembered if and when speculation about a Bush-led ticket is appropriate. Campaign developments have deepened Bush's antipathy toward Forbes--or at least toward the Forbes operatives. Should Forbes launch critical ads, "we will be ready," Bush says in a steely voice. But he has convinced himself that Forbes looks old-hat even to Republican voters who found him a fresh voice in 1996, and says Forbes will risk a backlash if he starts a negative campaign. Barring a major misstep, Bush thinks he has a lead in California's March 7 primary that no one can overcome--and that victory there should end the nomination fight.

If he prevails, he thinks Vice President Al Gore will be his general-election opponent. Labor's endorsement last week should give Gore a January win in Iowa, Bush says, and even if challenger Bill Bradley beats Gore in New Hampshire, as he might, the South will not support a candidate as liberal as Bradley--not even in the Democratic primaries. Democrats, he says, have one candidate (Gore) who looks "so contrived" and another (Bradley) who is "so low-keyed," that organizational factors likely will prevail--which spells victory for establishment candidate Gore.

And would he mind that? Bush just smiles.