Finally got around to reading John Miller's article in the current issue of National Review on McCain's VP prospects conservatives supposedly don't want to see on the ticket. It's a subscription-only article so here's a quick rundown:

Joe Lieberman: "In 2007, [Lieberman] earned a rating of just 8 percent from the American Conservative Union. That's only a single point better than Obama ... If he becomes vice president, the United States would be one heartbeat away from a Democratic administration."

Tom Ridge: "As a Republican congressman in the 1980s, [Ridge] amassed an unexpectedly liberal voting record ... More important, he failed to shape the culture of a new department [of Homeland Security] during its formative stages."

Charlie Crist: "Crist is not a conservative, but rather a populist who has assumed conservative positions on a few issues, such as taxes and crime."

Mike Huckabee: "[Huckabee's] economic populism turned off free-marketers. He would almost certainly inspire a new round of tedious speculation about whether the Christian Right is taking over the Republican Party ... It certainly wouldn't help McCain sway independents."

I think Miller gets most of these on the head. It's the candidates he left out that might still cause conservatives to worry. Tim Pawlenty, for instance, is coming under criticism for his less-than-conservative fiscal record, and, despite their turnabout late in the primaries, Mitt Romney is still not wholly trusted by many on the right. But neither, admittedly, are "untouchable."

Of Miller's "untouchables" I think we can cross Lieberman and Ridge off the list, while keeping a good deal of skepticism toward Huckabee. Crist has the tremendous advantage of having endorsed McCain just before his clinching victory in Florida and that could go a long way with McCain's decision.

One last point: As Miller notes, if there's an emerging consensus on McCain's VP prospects it's that he needs to pick someone who can assume the White House after he leaves office -- whether that be in 2012 or 2016. The Cheney Example might have served the GOP well while it lasted but it left a gaping hole when Republicans looked for another standard bearer and couldn't find one. Add that to the general sense that conservatives need a new leader and the pressure on McCain to look forward in his choice is considerable.