I think you're going to get very skewed results here with lots of bias. I wouldn't compare revolver to semi-auto to even single shot. There are varying degrees of accuracy that can be achieved by each group depending upon the quality of the firearm, barrel length, chamber design, etc. Semi autos will fall short in such a comparison if you decide to include accuracy at distances out to and beyond 100 yards. For the most part, they will fall completely out of the competition at those distances. Inasmuch, the results obtained from such a poll will be inaccurate and not very meaningful at best.
You might want to add qualifiers to this poll if you want it to have any meaning. Qualifiers such as; no magnums, 4 inch barrels or less, at distances up to 25 yards, etc.
By the way, don't be fooled; there are A LOT of single shot shooters out there! Probably the most active thread here is the NEF/H&R thread. Although they are not pistols, they are, nonetheless, single shots!
Hands down, my single shots beat them all! But here again, I'm shooting rifle calibers from them. Does that count in competition against a 1911 semi auto? NOPE!