Trailing Nico Rosberg by 33 points with four races to go, many pundits are starting to write off Hamilton but Wehrlein thinks that the Briton is still in the running.
"Both Mercedes drivers are geniuses in their own way," the Mercedes-backed Manor driver told Speed Week.
"I said it this way - one of them may be written off, but as soon as one of seems beaten, the other one has come back. So let's see how it turns out. For me, I think it's very, very exciting at the moment because of the way it goes back and forth between them.
"Unfortunately Lewis has been unlucky a few times, and it's not easy to make up those points, but as I said, neither of them can be underestimated."
The season continues this weekend at the United States Grand Prix.