Wow, this one's tricky. But I'm tempted.
I guess a lot of it would depend on what the motives were for the death match, if anything in particular was at stake, or if some grand reward was offered to the last one standing.
But if it was just a death match for its own sake...no external factors...my guess would go as follows:
Strong Bad--would start the whole thing, undoubtedly. He'd put in a good fight and perhaps cause some damage, but his participation would be short-lived. His destruction would either be the result of A) being taken out by someone smarter than him or
dying from a lack of foresight, a mishap due to his own poor judgment. We all saw how he fared against Pom-Pom.
Strong Mad--not as likely to provoke the beginnings of a fight, but could still cause significant harm to others due to superior brute force. Has the potential to destroy everyone else--only Pom-Pom would have a fighting chance against him. However, he could be easily outsmarted and defeated through alternative tactics.
Strong Sad--Likely not able to put up a good fight against everybody, but is intelligent enough to avoid a reasonable number of attacks. Found out, he's doomed.
Homestar--Again, not really likely to cause much damage onto others, but if he's just as athletic as they claim he is, he might be quick enough to dodge attacks. Could very likely defeat opponents by exhausting them. Then again, he probably wouldn't have a clue of what was going on around him, so...
Bubs--Simply put, very dangerous. He would likely get a gun and just go to town shooting everybody down. Plus, I always found him to be very cold-hearted in general so there'd be no stopping him unless someone bumped him off early. Unless the concession stand was at stake. Then he'd be the last man standing. No joke.
Coach Z--is a lover, not a fighter. Would most likely meet his demise by getting in the crossfire, trying to stop it. He'd actually have a better chance if he was attacked
directly , as he's quick enough to dodge/get away. Any damage he would cause would be unintentional on his part--he'd be likely to confuse everyone else into vulnerability with his stories or just scare everyone by showing what was under that track suit.
The Cheat--would succeed by doing what he does best--by cheating. His battle tactics would be more secretive and stealthy--he would be harming others without them even aware of it, perhaps by setting one person against another and leaning back to watch the results. But being small and weak otherwise, it's unlikely he'd make it to the end.
Marzipan--Not as weak as you'd think. Nobody thinks the Water Drop Torture is all that bad...but after a while it dents a hole in your skull. She'd fight through nagging. The longer she stayed in the game, the better she would do.
The KOT--oh dear. Very unlikely to win...unless the prize was a buffet table. Then he might just literally eat his way toward success.
Pom-Pom--Appears to have the greatest advantages--intelligence and outstanding fighting skills. He would only lose under bizarre circumstances--like, if his cell phone rang during the fight. I don't think Mr. Popular himself would ever miss a call. If that's the case...then all you need is a pin. And I think the one most likely to defeat him would be...
Poopsmith--The quiet, unexpected guy ALWAYS wins. You don't know just how well he can use that shovel.
Homsar--Um...I don't think he can actually die. He COULD be locked into a safe and dumped in the ocean, though. But that would take effort.
And now I have the Ultimate Showdown of Ultimate Destiny stuck in my head.
Log in
Wiki
FAQ
Search
, he's all bouncy so pretty much nothing hurts him, and he's a black-belt. (He's also got that gun from Yello Dello) 
and 
I would say also have a decent chance. Oh, or maybe homsar, w/all his reality defying powers.
then why don't you vote for him?
