Under the Dome is the latest to weigh-in on the notion that Dems in general and John Edwards in particular have an advantage over the Red staters in political use of the Web.

And to that I say — So?

Even if true, any edge will melt away as the campaign advances.

Recall that once upon a time Howard Dean was thought, hands down, to being leading the tech edge in politics. It got him started and sustained and spread his message, but it was ultimately useless in actually winning him votes. That is because all presidential campaigns are top-down affairs. They can be no more sustained by the grass roots than a White House can be.

And that is what presidential campaigns really are — a series of shadow executive staffs auditioning for real power. The staff that does the most convincing job of portraying a competent and reasonably in-touch operation, beginning with a believable and non-offensive CEO, gets to move into the White House for four years. Repeat.

Right now I think the Left has more true believers who really think what they do and say online influences a presidential campaign. It might matter now, in the ridiculously early stages of May 2007.

But when the also-rans are wrung out and big money starts to call the shots, all the MySpace pages and blogs in the world will not matter. More precisely, they will not matter in a positive policy-making role. Instead online campaign arms will be used, and should be used, to attack other campaigns, leak damaging info and otherwise cause trouble on the cheap. However, it is fantasy to think that any candidate will read a summary of speech he or she is about to give and think, “But what will the blogs think?”

Dean had tons of small donors in his base and his MeetUps — anyone remember MeetUp? — were positively electric there for awhile. But as his campaign grew and become more “professional,” Dean was soon captured by the same tired policy box that defines American politics. Still defines and constrains it. Look what happened to Ron Paul for daring to voice what was once a relatively common Republican non-interventionist take on foreign policy — one that has enjoyed a re-birth in many online forums in recent years. But Paul mentions it in South Carolina and the reaction is as if he called the Holocaust a hoax.

Were the Net in 2007 up to the task of setting and defining an agenda for a presidential campaign, there’s is no way Paul gets that reaction.

I’m not sure why, but I think 2008 will be the last presidential campaign of the Old Republic. Something is going to change in a big way before 2012 — has to considering the federal entitlement bomb that will go off, continued high government spending, and a military stretched increasingly thin across the globe.

Maybe we will ditch the Electoral College by then or impose a federal value-added tax as a way to both pay for entitlements and capture revenue from non-citizens.

And vote during the commerical breaks of Hemisphere Idol.