LFF

LFF, aka the Leach Fanbase Factor, is to 3-or-more way polls what SFF is to 1v1 polls. The basic idea is that whereas in a one on one situation between two characters sharing a fanbase the stronger character will make his weaker counterpart look bad, in a four way poll both characters sharing a fanbase will make each other look worse.

Here is a real-life example using two characters we know plenty about: Link and Cloud. In a 1v1 setting the result between these two the result would be


 * Link - 54%, Cloud - 46%

Now let's add four more characters into the poll: Ganondorf, Zelda, Tingle, and Midna. The result would be something like this:


 * Cloud - 42%, Link - 41%, Ganon - 7%, Zelda - 7%, Tingle - 2%, Midna - 2%

Even though he was given four opponents he can SFF nearly to death, the small amount of support from the Zelda fanbase that those four alternatives received "leached" enough strength away from Link to make up the sizeable gap between himself and Cloud, resulting in his second place finish.

The argument against LFF is basically, "but including non-Zelda characters would hurt Link way more!" While this is true, the point is that these new characters would also hurt Cloud way more, resulting in a win of comparable size to the original 1v1 matchup. Let's run an example using four new characters who don't share a fanbase with Link or Cloud: Snake, Dante, Ryu, and Kerrigan. That 6-way would end with this result:


 * Link - 26%, Cloud - 23%, Snake - 18%, Dante - 15%, Ryu - 13%, Kerrigan - 5%

Yes, not being able to SFF his opponents hurt Link badly, costing him 15 percentage points off his old total. But having to compete against something other than the Zelda fanbase hurt Cloud far worse, as he lost a full 19 percentage points, well more than enough to cost him the victory.