And the choices are just as tough as the ones for the "Favorite SF&F Hero" poll were. See them (and vote)
here.
I think I'm gonna go with Donna, because, well, Donna. :)
However, awesome as these characters all are, I wish Martha and/or Tosh (to name a couple characters from DW/TW fandom) had made it to the list. To put it gently, there isn't a lot of diversity being represented. (The "Hero" poll is nearly as homogeneous, I realized, when I went back to look.) I don't think it's SFX being obnoxious, just another reminder the whole genre could do with a little diversification. Good to see LBGT choices on both lists, at least!