Which candidate was most supported | You mean the candidate who got the highest support rate? | yes which candidate was most popular
SELECT t1.name FROM people AS t1 JOIN candidate AS t2 ON t1.people_id   =   t2.people_id ORDER BY t2.support_rate DESC LIMIT 1
most supported or most popular candidate refers to MAX(support_rate); candidate's name is retrieved by joining people and candidate tables on people_id;