Quite a few do, actually. The first person to accomplish the feat, a noted photographer and writer named Grancel Fitz, did it in the 1930s with a .30/06, and that would serve as well today. Some other nominees would be any of the .30 or .33 magnums.
Outdoor Skills – Hunting Q&A
Does any one rifle have the capability of taking all 30 species of North American big game?