What is the number of students who have class senator votes in the spring election cycle?
SELECT count ( * )  FROM STUDENT AS T1 JOIN VOTING_RECORD AS T2 ON T1.StuID   =   Class_Senator_Vote WHERE  T2.Election_Cycle   =   "Spring"
number of students who have class senator votes in the spring election cycle refers to COUNT(*) when Election_Cycle = 'Spring'; joining STUDENT and VOTING_RECORD tables on StuID = Class_Senator_Vote to filter records for the condition.