No way, Mario is a fat ass that can run as fast as my great-grandma in her wheelchair. Sonic may be fast, but once you get going your bound to fall straight off a cliff at some point.
This is like the Children's Story: The Tortoise and The Hare. Mario will keep on truck-in through as long as you give him his minutely dose of mushrooms. Sonic then plows his ass down in search of something shiny.
My estimation, Sonic falls of the fucking ledge and dies while he lands on spikes and loses all his rings, and Mario ends up thinking 'fuck this shit'. Then leaves to get a hoagie. So all in all, cho loose every time.