You could do a thing where 5 is neutral, 10 would be strongly in favor, 0 strongly against, etc.
A poll would be best because it tallies responses.
The poll format is also good becaue it gives people the ability to clarify their opinion.
In a perfect world for me, there would be a limit on how much you can write. Get in, make your point, get out.
But that part would be hard because there's no device with which to limit the length of responses.