If the comedian starts using that ability to make people think the politician said something they didn't say, then the comedian is guilty of fraud.
Also, "humans can do it" is not a reason to allow AI to do the same thing. GenAI systems can do things at high speed 24 hours a day forever and the fraud potential is much much much higher.
Thought experiment: If I steal someone else's credit card to buy things (example from FindLaw [1]) that I won't use just to harm my victim, would I be committing fraud? Or would only the non-fraud charges apply?
Don't trust findlaw.com or a dictionary definition. It doesn't matter if you personally gain. Here is the actual text of the US federal fraud statute [1]
"....obtaining money or property by means of false or fraudulent pretenses, representations, or promises....."
