George W. Bush and John McCain are putting one of my political axioms to a severe test. Over the years, I have come to believe that politicians are very good judges of other politicians; that if you want to know the worthiness of candidates seeking higher office, ask the people who have served with them.

That is why it was so impressive last winter to see all those Republican governors move early to anoint the governor of Texas as their choice for the presidency in 2000.

They owed Bush nothing. Many other options were available--including the safety of sitting tight until the contest developed. But some of the ablest in the group, people such as Mike Leavitt of Utah, Marc Racicot of Montana and John Engler of Michigan, stepped forward to mobilize their colleagues on behalf of Bush way back in February.

They judged he had the right stuff to go the distance, not just to a first-ballot nomination victory in Philadelphia but to the White House--because all of them told reporters they were determined to find a winner this time.

The problem with the theory is that while Bush's endorsements and his campaign treasury (filled with help from those same governors) scared away several well-credentialed rivals before the first vote was cast, he simply does not stand out in the debates among the candidates who remain.

The second such forum, held here last week, was the same as the first, in New Hampshire. Bush repeated chunks of his memorized stump speech, whether they fit the question or not, and made not the slightest effort to demonstrate either intellectual heft or political adroitness.

It may not cost him the nomination. As I've said before, his great talent lies in his face-to-face campaigning with individual voters. The morning after the Arizona debate, I watched him work the room for 40 minutes at a breakfast sponsored by the state Chamber of Commerce. He had a friendly word for everyone, a pat on the back, a squeeze of the arm. As he left each round table of 10 guests for the next, the people he'd just been with wore happy, dazed expressions of star-struck admiration.

That is a gift. With his campaign seeming confident that Bush will easily defeat the challenge from Steve Forbes in the Jan. 24 Iowa caucuses, he can spend most of next month in New Hampshire, which votes on Feb. 1. His mastery of one-on-one campaigning may give him the support he needs to withstand Sen. John McCain, who is skipping Iowa in favor of stoking the surge that has brought him even with Bush in New Hampshire polls.

But serious doubts have been planted about Bush's ability to win in November: If he can't match wits with Gary Bauer or Orrin Hatch, how will he do in debates against Al Gore or Bill Bradley? He has to do better delivering his message on TV--or else.

Meantime, McCain tests my theory in a different way: Those who know him best have wildly differing views about his suitability for the presidency. McCain has been endorsed by such serious and independent-minded Senate colleagues as Chuck Hagel of Nebraska and Fred Thompson of Tennessee. They backed him on his merits, not to help their careers. And McCain also is admired by many Senate Democrats.

On the other hand, there are many equally large-minded legislators among the vastly larger numbers of House and Senate Republicans who have passed over McCain and given their support to Bush. Some notably fair-minded people who have served with McCain over the past 16 years have strong reservations about seeing him in the White House.

The same thing is true here in Arizona. McCain has devoted fans. At the Chamber breakfast, financial planner Joe MonteCarlo told me, "I've followed John's whole career. He's a fighter. I like that." On the other hand, Arizona State University professor Tom Shaffer said, "McCain and his people have more enemies here than anywhere else; they've been awful tough on people. I think George Bush will win the [Feb. 22] primary easily."

You find the same split among veteran politicians. Before the debate here, Sen. Jon Kyl and Rep. J. D. Hayworth, speaking on behalf of everyone in the Arizona Republican congressional delegation, said McCain's release of his voluminous medical records answered every legitimate question about his emotional stability and should close off further criticism of his temper.

On the other hand, former House minority leader John Rhodes, whose retirement in 1982 opened up the House seat that launched McCain's career, told me he is supporting Bush rather than McCain, because he is persuaded "John can't win in November."

You can see why I'm puzzled. Anybody have a better theory?