One of those low-grade-fever, under-the-radar discussions that often consume the chattering classes involves the possibility that the Republican Party will offer up John McCain as the successor to George W. Bush in 2008. It’s an especially interesting topic to us political junkies who know (a) how much savage hatred was built up in 2000 between McCain and the movement conservative/K Street/theocon establishment backing Bush; (b) how often McCain has violated conservative litmus tests on domestic issues ranging from tax cuts to global climate change to ethics legislation; and (c) how tempting it is to McCain’s old GOP enemies to bring him back into the establishment to save it from total immolation in 2008.I’ve already weighed in on a TPMCafe discussion of McCain’s future, but was prompted to say more here by an interesting assessment of McCain’s rapproachment with conservatives written by Byron York of National Review, published by The New Republic.York is a very good old-school reporter who knows the conservative world intimately, so I’ll take his word for it that McCain’s efforts on Bush’s behalf in 2004; his base-pleasing outspokenness about the righteousness of the war in Iraq; and the recent conservative convergance with the Arizonan on the fiscal profligacy of the congressional GOP; are all factors that cover a multitude of McCain’s past and present heresies against Republican orthodoxy. But I submit those heresies–which include McCain’s sponsorship, with Joe Lieberman, of the climate change legislation conservatives hate passionately–remain a bar to a McCain run in 2008, unless he goes far out of his way in the future to tack back to the Right. The other factor, of course, is exactly how desperate Republicans are becoming when they think about 2008. Do they embrace their ancient intraparty enemy over their friends? Will they demand McCain bend the knee on a variety of conservative litmus tests? How many assurances will they require about the shape and the staffing of a potential McCain White House? (Will my colleague The Moose, for example, be banned from grazing among the canapes at White House receptions?).My own gut feeling about the current conservative flirtation with McCain is that it’s all a matter of hedging bets. The Right will look high and low for a presidential alternative to McCain, but the big priority is to make sure they get a sufficiently clear set of commitments from him to make the competition as insignificant as possible.For us very interested outsiders in this Republican debate, the major question is how big a piece of his own persona McCain has to repudiate to attract GOP forces who’d rather try to tame and train him, than to actually listen to his words. And for McCain, the question is how far he’s willing to go to make his own proud and independent words meaningless.