But there was a subtext to the book, and the event: Frist is a man of burning ambition, eager for a national role and, I am guessing, a place on George W. Bush’s ticket in the off-chance one were to open up in the summer of 2004.

Frist’s decision this week to guard the president’s flank on human cloning dramatizes his desire to be seen as a Bush Team Player. The medical promise of stem-cell research was overplayed, he said, and the moral imperative clear: Congress must ban the cloning of human embryos no matter what the purpose. Frist’s move was not unexpected, but crucial. Without it, Bush would have little chance of winning a cloning-ban vote in the Senate.

In a 24/7 world, presidential politics never ends. This weekend, the Democrats hold their first major “cattle show,” in which as many as a half dozen wanna-bes parade their stuff before reporters and party insiders assembled at Florida’s Democratic State Convention. But there is an even less visible campaign underway among Republicans: a NASCAR contest for drafting position in the slipstream of Bush’s Car 43. So far, the loud engines in the pack are Frist, Colin Powell, John Ashcroft and Tom Ridge.

The first lap, 2004, is provisional, of course. Dick Cheney isn’t going anywhere, at least not of his own free will. His health is good, his diet and exercise well-supervised. He prefers to be inscrutable, but when I saw him on a campaign swing in California recently, he couldn’t hide how much he relishes the veepship as he has crafted it, at the center of the action. Cheney doesn’t love public life, but he loves the exercise of power. It would take a crowbar and a court order to get him off the ticket in 2004. Loyal liegeman though he is, he won’t offer to stand down as the GOP convention approaches. Nor would he go quietly if asked to leave.

No one expects Bush to ask, but you never know. There will be pressure in the Republican party, and perhaps in Karl Rove’s vaunted “Office of Strategery,” to look for more electoral oomph on the ticket. Think of Cheney as a kind of human booster rocket, an expendable vehicle chosen to reassure voters worried about Bush’s lack of global experience. Bush’s competence isn’t an issue any more, and, if the war on terrorism is a bust, Cheney won’t necessarily be the White House’s best defender.

So it pays to be in the right place at the right time, should that time arrive–either in 2004 or beyond. Not surprisingly, the key early players for now all have some important relationship to the world wide war on terrorism. Here’s how they stack up. POWELL. No one expects the secretary of State to work miracles in the Holy Land. But if he can broker a workable, lasting ceasefire, he will earn the plaudits of the world–and maybe even the grudging respect of Republican conservatives who have never trusted him, and who, for a variety of reasons (including their alliance with hard-liners in Israel), aren’t eager to see his shuttle-diplomacy mission to the Middle East succeed.

Powell almost ran for president once but held back in part because his wife, Alma, feared for his safety. But if he can travel to the West Bank to meet Arafat, he presumably can take the risk of campaigning in, say, New Hampshire.

ASHCROFT. Rove rues the failure of Christian conservatives to turn out in heavy numbers for Bush in 2000. By his calculations, some 19 million such votes were available to the ticket, but only 15 million voted for it. Raise those numbers even by a little bit and the Bush-Cheney ticket would have won handily; raise the numbers by a lot, and you’re talking landslide.

Ashcroft was running hard for president in 1999, when he was run over by the much better funded and certifiably Bible-believing governor of Texas. Ashcroft was in the Senate at the time, and his departure from the presidential race–and endorsement of Bush–was the single most important little-noticed event of the entire campaign since it allowed Bush to essentially lock up the religious conservatives early.

As the hard-charging attorney general, Aschroft has won surprisingly decent (or at least not wildly antagonistic) reviews from Manhattan-based Big Media. One reason: he is indeed more thoughtful than his critics have given him credit for. Another: when the Twin Towers collapsed, so did the old-line liberal concern about prosecutorial abuse.

RIDGE. The former governor of Pennsylvania almost made it onto the ticket in 2000, until he was blackballed for his pro-choice views by the bishop of Erie. But it’s easy to see why, on paper, Bush almost went with Ridge: he’s Catholic, played football at Harvard, was wounded in Vietnam–and hails from a state that the GOP has come to view as a kind of aging El Dorado, full of cultural conservatives who nevertheless vote Democrat. Bush and Rove remain intent on winning Pennsylvania, which the president has visited more times than any other state except Florida.

With an eye on Pennsylvania, and in search of a guy he trusted with management experience in government, the president called on Ridge to head the Office of Homeland Security. He arrived in Washington with great fanfare and to continuing confusion about the powers and duties of his job. He got poor reviews for his handling of the anthrax situation and has been all but invisible since. On the other hand, invisibility is a good thing for Ridge politically and for the country generally: it means a lack of catastrophe.

FRIST. Bush doesn’t need help in the South, which he swept in its entirety, but he especially enjoyed winning Tennessee, home to his foe, Al Gore. But Frist is a formidable character, a rising star hard to ignore. An intense fellow who did more than a 100 heart and lung transplants in his medical career, he wastes no time in going after what he wants–and doing it his own way.

Early on, Frist got crosswise with the White House, floating his own plan for stem-cell research before Bush, with much fanfare, unveiled his. But Frist is trying hard to be cooperative, do the mundane dirty work that earns party points and lays the groundwork for later. For example, he chairs the GOP’s Senate campaign committee for 2002. In that capacity he travels the country, meeting the financial and political heavy hitters who could help elect Senate candidates–and Frist. He also talks to the president, the vice president and Rove on a regular basis about politics.

It’s a topic Frist knows a good deal about, but he’s in a hurry to learn more.