Here in Chicago area, there is only one deliverer of power, Comm Ed. However, there are many suppliers of the electricity itself. And many of the suburbs, mine included, have worked to get consolidated electricity supply alternatives on a village/town-wide basis. The process typically is started with a voted referendum to seek a change. I think all have passed, I know our town passed its referendum. The village then goes out to the market to get the best deal they can for the people of the town. Once selected, it then becomes an opt out procedure. If you do not opt out, the new supplier will automatically become your new supplier of power in several months. We voted back in Feb, our new supplier starts next month. The power cost will be about 40% less. The delivery charge will stay the same since it is still Comm Ed. The bill will continue to come from Comm Ed, any service calls will still be Comm Ed.
I would say most of the towns/villages around here have done similar.