Two Republicans will be facing off in a primary to replace Sen. Greg Ball.
Former Assemblyman Robert Castelli announced today that he is going to challenge Yorktown Councilman Terrence Murphy in a primary.
Castelli says he can do the job even though Westchester Republicans gave the 40th Senate District nomination to Murphy.
The Democratic candidate is Justin Wagner, of Croton, who lost to Greg Ball two years ago.
Ball announced plans to not seek another term last month.