To be honest, I've now lost count of how many candidates there are. Tommy Thompson is out, Huckabee is up, Fred Thompson is almost in but already fading. (But, the longer he waits, the more residuals he accumulates - and the other members of the cast lose out on equal time rules as innocent bystanders as soon as he announces..).
Dem's seem to be down to two already - Hilary and Obama - but I still think that Al Gore may be running the most brilliant election campaign in history. Appear in award winning movies, write a book, save the world, rescue the party from about the only candidate they could run that the Republicans might actually be able to beat.....I still consider him a serious stealth candidate.
Dems are also beginning to reposition as it appears that the surge may actually be working. Who knows, by election, the party of Henry "Scoop" Jackson, Sam Nunn and John Kennedy may re-emerge....The war has been a mess, Bush/Rumsfeld screwed up, but the military may prevail despite all that, and I don't believe that Americans really want to see us lose and slink out a la Viet Nam.
So, I don't think running on lose and withdraw is a proposition that draws votes.