Some Republicans -- call them single-criterion Republicans -- favor John McCain's presidential candidacy because he seems to satisfy their sole standard: Which candidate is least like Clinton?

Surely, they think, the un-Clinton is McCain, whose character has been tempered in the furnace of a POW camp; whose ability to pander has supposedly so atrophied through disuse that he would see the heavens fall rather than court Iowa by supporting ethanol subsidies; who, ever an oak, never a willow, insouciantly goes his own way.

Trouble is, his own way is frequently the way favored by the major media. For example, his grand passion, campaign finance reform, would enhance the media's power by leaving them, unlike most other advocates of political causes, exempt from government regulation of political advocacy. The media call McCain a "maverick," even though he seems to be, oxymoronically, a predictable maverick.

Hence the deepened dismay among McCain admirers when on Aug. 20 the San Francisco Chronicle reported this from an interview with him:

"I'd love to see a point where [Roe v. Wade] is irrelevant, and could be repealed because abortion is no longer necessary. But certainly in the short term, or even the long term, I would not support repeal of Roe vs. Wade, which would then force X number of women in America to [undergo] illegal and dangerous operations."

Well. When, and in what sense, does McCain think abortions are "necessary"? Why does he think that if Roe v. Wade were overturned, thereby re-establishing abortion as a matter subject to state regulation, that states would outlaw, or even seriously restrict, first-trimester abortions, which are about 88 percent of all abortions? (Asked if he could think of a single state that would outlaw them, Rick Davis, McCain's campaign manager, said: "No.")

By what reasoning does McCain support first- and second-trimester abortions as a fundamental constitutional right (Roe v. Wade), but also favor (as he does) banning third-trimester abortions? And how does he read Roe v. Wade to conclude that what the court said is compatible with a ban on all third-trimester abortions?

The next president may nominate three Supreme Court justices. But what should conservatives conclude about McCain's likely Supreme Court appointees? Many people who are pro-choice nevertheless regard Roe v. Wade as execrable constitutional law. But judging by the Chronicle report, McCain does not believe the court's discovery (in "judicial dust," says Rep. Lindsey Graham of South Carolina, a McCain supporter, speaking in defense of McCain last Sunday) of a "fundamental" right to abortion should be overturned to reassert proper constitutional reasoning.

Finally, how can McCain square what he told the Chronicle with the answer "yes" that he gave last year in response to the question, "Do you support the complete reversal of " Roe v. Wade? Or with this, from Feb. 25 and July 22, 1998: "I am a lifelong, ardent supporter of unborn children's right to life."

His voting record reflects that. But Emily Dickinson comes to mind: "I believe and disbelieve 100 times in an hour, which keeps believing nimble." Such nimbleness may serve poetry better than it serves the presidency. Two days after the Chronicle report, McCain's campaign released this statement:

"I have always believed in the importance of the repeal of Roe vs. Wade, and as president, I would work toward its repeal . . . but that . . . must take place in conjunction with a sustained effort to reduce the number of abortions performed in America. If Roe vs. Wade were repealed tomorrow, it would force thousands of young women to undergo dangerous and illegal operations. I will continue to work with both pro-life and pro-choice Americans so that we can eliminate the need for abortions."

As president, his first Supreme Court nomination could cause Roe v. Wade to be overturned, thereby restoring state powers to regulate abortion, with perhaps negligible regulation by most states. But regardless of states' actions, it is unclear how overturning Roe would "force" anyone to have an abortion, let alone force "thousands" to have "dangerous and illegal" abortions. And, again, it is unclear what McCain means by eliminating the "need" for abortions.

All this confusion may not reflect any political calculation by McCain (such as advantage in pro-choice California's March 7 primary). But even if it reflects only muddy thinking, it is one more reason why many who want to support McCain because of his spiritedness must remind themselves of Stephen Leacock's admonition: "Many a man in love with a dimple makes the mistake of marrying the whole girl."