SELECT party FROM representative GROUP BY party HAVING COUNT(*) >= 3
What parties have at least three representatives?
CREATE TABLE election (
    election_id number,
    representative_id number,
    date text,
    votes number,
    vote_percent number,
    seats number,
    place number
)

CREATE TABLE representative (
    representative_id number,
    name text,
    state text,
    party text,
    lifespan text
)