How many Republican held US Senate seats up in 2020 that Democrats have a chance of winning?

1)AZ special(McSally-R) Kelly-D
2)CO(Gardner-R) Hickenlooper-D
3)ME(Collins-R) Gideon-D
4)NC(Tillis-R) Cunningham-D
5)GA special(OPEN Isakson-R) Lieberman-D
6)GA regular(Perdue-R) Tomlinson-D
7)IA(Ernst-R) Greenfield-D
8)KS(OPEN Roberts-R) Bollier-D vs Kobach-R
9)KY(McConnell-R) vs McGrath-D
10)SC(Graham-R) vs Harrison-D
11)TX(Cornyn-R) vs Hegar-D
12)WV(Moore Capito-R) vs Ojeda-D