I believe the EPA uses 100% gas with no ethanol for the tests.
Most stations have/sell only ethanol blended fuel. I know Illinois requires that the pumps be marked if the fuel contains ethanol.
I do have a station that sells both.
My 04 Grand Cherokee V8 will get 1-1.5 sometimes 2 MPG better mileage with 100% gas. So I would assume with ethanol 19 mpg (city) Cherokee V6 will be around 17-18 mpg vs. EPA 19 MPG.
I'm looking toward testing this out when my ordered one gets built.