Missing: Republican warchest

If Hilary or Obama are going to win, there has got to be a 3rd party candidate that rivals Ross Perot's vote-gathering ability.
Or the GOP has to nominate Tancredo.

Not sure about that. If Kerry had won Ohio, he'd be president today. Bush squeaked by in 2004 with 279 electoral votes (270 makes you president).

2004 was pre-Katrina, pre-Iraq meltdown and Rove had spent the previous 4+ years building a formidable election ground game. And Ohio was dominated by the GOP at the state level; now it's dominated by the Democrats.

I don't see Obama or Hillary as weaker than Kerry in states that Kerry won closely (e.g., Wisconsin, Pennsylvania).

It's possible that McCain/Romney/Giuliani will be more appealling to voters than Bush was in 2004 -- but I don't see that as obviously the case. Sure, they're more appealling than post-Katrina, post-Iraq meltdown Bush, but that's not saying much.