We saw part 1 Kakashi beat off severial ninja almost effortlessly in the Chunin exams, and fight for pretty much the entire time without any serious injury. We also saw part 2 Kakashi fight against the entire 7 swordsmen (unique ninja) backed by two powerful bloodline ninja, and still came out fairly fine, fine enough to go into a fight with Tobi, though largely playing a more passive role until the opening presented itself.
I don't believe he could solo the ninja then as well as Obito did. A combination of the suit, Hashi DNA (Which apprently makes everyone gods) and his superior MS made all that possible. However, I believe that killing these Jutsuless, low fodder ninja is within his range, though he would be completely out of it afterwards. To be honest, we don't really see him in the same situations that often to know that well, but again, in part 1 he was shown to be extremely capible of beating off "basic" ninja almost effortlessly. He took care of the Hidden Mist demon brothers in pretty much a blink of an eye.
Though again, if any of the severn swordsmen are present, it would greatly, complicate matters.