Videos #2, #5, #6, #9, #11, #15, #16, #18, #19, and #20 are in the bottom 50th percentile. (Meaning 6 or less people have guessed them correctly.)
Because this is a harder round, I will tell you where the song comes from. (As in what country the artist is from.) This is for the bottom 50th percentile videos ONLY!
Video #2 - California
Video #5 - California
Video #6 - England
Video #9 - California
Video #11 - Ohio
Video #15 - Texas; Illinois
Video #16 - Wisconsin
Video #18 - Nevada
Video #19 - Oklahoma
Video #20 - Georgia
I don't think I've ever seen a hardcore stan of hers around here, but I have seen one or two people use this video or pictures of her in their avatars.