How many Republican held US Senate seats up in 2020 are vulnerable to Democratic takeover? [View all]

1)AZ special(McSally-R) Kelly-D
2)CO(Gardner-R) Hickenlooper-D
3)GA regular(Perdue-R) Tomlinson-D
4)GA special(OPEN-R) Ossoff-D
5)IA(Ernst-R) Franken-D
6)KS(OPEN-R) if Kobach-R vs Boyda-D
7)KY(McTurtle-R) McGrath-D
8)ME(Collins-R) Gideon-D
9)MT(Daines-R) Schweitzer-D or Bullock-D
10)NC(Tillis-R) Cunningham-D
11)TX(Cornyn-R) Hegar-D