Among the female legislators, what is the percentage of the senators in Maine?
female refers to gender_bio = 'F'; percentage = MULTIPLY(DIVIDE(SUM(type = 'sen'), COUNT(type)), 100.0); senators refers to type = 'sen'; Maine refers to state = 'ME';
SELECT CAST(SUM(CASE WHEN T2.type = 'sen' THEN 1 ELSE 0 END) AS REAL) * 100 / COUNT(T2.type) FROM current AS T1 INNER JOIN `current-terms` AS T2 ON T1.bioguide_id = T2.bioguide WHERE T2.state = 'ME' AND T1.gender_bio = 'F'