Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE votes (contestant_number VARCHAR, state VARCHAR)
TABLE: CREATE TABLE contestants (contestant_number VARCHAR, contestant_name VARCHAR)
TABLE: CREATE TABLE area_code_state (area_code VARCHAR, state VARCHAR)

### Question ###
List the area codes in which voters voted both for the contestant 'Tabatha Gehling' and the contestant 'Kelly Clauss'.

### Accurate SQL ###

SELECT T3.area_code FROM contestants AS T1 JOIN votes AS T2 ON T1.contestant_number = T2.contestant_number JOIN area_code_state AS T3 ON T2.state = T3.state WHERE T1.contestant_name = 'Tabatha Gehling' INTERSECT SELECT T3.area_code FROM contestants AS T1 JOIN votes AS T2 ON T1.contestant_number = T2.contestant_number JOIN area_code_state AS T3 ON T2.state = T3.state WHERE T1.contestant_name = 'Kelly Clauss'