I'd say the vampires of True Blood would win because the vampire's in True Blood are much stronger and faster.

TRUE BLOOD no doubt about it

Eric Northman could fight off the entire cullen household. Hands down (or cheeks up!)

The Vampires of True Blood would win defiantly

The vampires in True Blood are definitively the better vampires, but when one thinks about it...
The "vampires" in Twilight can't be harmed by anything else than a "werewolf's" teeth or another vampire's fangs. They could just bring a stake and stab the other, or silver and tie them down until dawn. But I guess they wouldn't have the brains for that, so the vampires of True Blood would totally win :3

The cullens would win because they have more powers in each vampire.

Easy True Blood