I first heard this in "Don King's Prizefighter for Wii", where he says, if I'm transcribing correctly:
If I can do it, you can do it!
The heart would say, in America anybody can do it!
Trying to Google this first sentence I'm getting so many hits that I've no idea where to start looking.
My native language is German, and the corresponding translation of this sentence is rarely used in German. And when I find it used in German, it might well have been translated from English.
So I'm curious whether it might come from a single source?