Larry Sabato is like a fisherman when the fish aren't biting--the futility of the act doesn't mitigate the urge to do it.

Literally anything could happen between now and the 2008 election cycle.

Let me instead point out some signposts that might determine who would be a viable candidate in the next presidential election.

1. Do Republicans pick up Wisconsin, Michigan and Minnesota's governor's races this year? The reason this is important is because if as expected, Republicans start out with an electoral vote advantage, I think the primaries become correspondingly more important and so do the issues of the primary voters. John Kerry's victory in the primaries underscores this paradigm as many, many voters explained their votes for him by saying that they though "others (meaning Republicans and conservative Democrats) would vote for him. The perception that the general election will be easy or tough changes what people will value in a candidate. I would say that McCain and the perceived more-liberal Republican candidates will do better if 2006 is a bust for the party, and worse if the electoral math favors a generic Republican win.

2. What will be the security situation of the U.S. in 2007 and 2008? Insecurity and war favor the Republicans, peace favors the Democrats. This isn't a binary choice. Insecurity is relative. If we still have troops in Iraq and sporadic but declining violence, I think that counts as "peace", but if the situation in Iran continues to escalate, people are going to feel queasy, and the oil factor in a conflict with Iran is also a major issue. A severe crisis rolls over all the pet conservative issues, as the war did "small government". McCain has the biggest advantage here and Guiliani could do well. As we move towards the other side of the security continuum, the more classically acceptable conservative candidates rise to the surface.

3. Who will appeal to the activist base? Ultimately, in a free-for-all, the guy with the best organization is going to win the day. Should we come out somewhere in the middle on the above two criteria, organization is going to be the key to victory. This is particularly difficult to predict at this point, especially since so few of the probably candidates have their own highly-motivated constituency at this point, yet prospectively at least, Mitt Romney could do very well here. Not only is Romney an exceptional organizer, he also has an in with a low-key, but extremely influential and dynamic constitency--the Mormons. Some have estimated that 25% of all Republican volunteers in 2004 were Mormon. This was one of the very early advantages of the George W. Bush campaign--he had the similarly dynamic and motivated Evangelicals on his side and willing to work for his election.

After its all said and done, the person who looks best on paper at this point, who could reasonably perform well under a variety of conditions, is Condoleezza Rice. She has the security credentials and tremendous appeal across a broad swath of American constituencies, including some not traditionally under the Republican tent. Even with that being the case, she is subject to the same fortunes of fate as everyone else.