I believe if it was generic Space Marine VS generic Jedi, it would be Space Marine every time. While Jedi are empowered by a mystic energy field that binds all of creation together, most of them do not have a great capacity for extreme use of Force Powers, leaving them as augmented beings, but still very much within the peak end of normal human abilities (I’m using baseline humans for this debate.) We actually have accounts of normal humans beating Jedi, such as Jango Fett single handedly killing seven Jedi. A generic Tactical Space Marine however is a monster of genetic and mechanical might. Augmented by 18 gene-seed operations, they are now so fast they can dodge hypersonic bullets, see in low-light conditions, follow targets by scent alone, spit acid, and throw grenades the size of a human head farther than a grenade launcher can shoot. This, coupled with their weapons and armor, the bolter, which shoots .75 self-propelling hypersonic rounds that detonate within the enemy, and the Tactical Space Marine armor, which augments their already impressive strength and speed, and provides unparalleled protection (and also includes adrenaline shots, sensors, and even food packs), and also considering how an average Tactical Space Marine usually has over three centuries of combat experience, first as a scout, then a heavy weapons specialist then a close combat veteran, I’d say the generic Jedi loses every time, unless we’re talking about someone like Luke Skywalker, Avatar of the Force. 🙂