Hi Percy,
I think you've presented a very cogent picture of the problem. However, you've also neglected one critical element. Read Truthlover's post for a typical example. When even someone as well-read and articulate as TL can't see it...
In a nutshell, there is a deep, probably unbridgeable chasm within the Republican party that only two dem candidates in recent memory have even recognized, let alone attempted to exploit: that between the political (for lack of a better term) and social conservatives (aka carpet chewers). John McCain saw it, and ran a campaign designed to appeal to the "political" wing - which may in fact be a near-majority. The fact that he was an inept boob who managed to alienate everybody is what did him in. The other was Ross Perot, who nearly succeeded. Unfortunately (or fortunately, depending on your political bent), Perot is probably clinically insane, and quit in a huff over some perceived slight magnified in his mind to astronomical proportions.
The other issue is that Republicans, more so than Democrats, have traditionally "rallied 'round the flag" when it comes down to "us vs them" in a presidential final race. Even that is a near-run thing: witness the last election - "weak" Republicans deserting the party or simply staying away in droves is what caused the election to be so close in the first place. Kerry, if he has any chance, has to develop a platform that speaks to this disaffected, very large minority, of "political" conservatives. So far, his entire platform seems to be "I hate Bush. Vote for me." He's gonna have to do better than that, or this next election is likely to be nowhere near as close as the previous one.
My two kopeks.