Andymad is correct. Madonna while during the Pre-Madonna years as an adult always had gay influencers on her... her teachers, her friends, etc., that is one aspect. She was always on the side of us gays from the beginning.
Now, in general, the pop stardom and appeal aspect of the gay draw to Madonna was as strong and alluring as gays to Barbra or Judy or Liza or Cher or Bette... there is just something from a pop star aspect that was like a magnet for us to be attracted to Madonna's light. I have not found in modern post madonna history many other types of magnetisms... For some, I guess Gaga or Beyonce for sure, likely Britney... But all of them in one form or another still look up to Madonna as their role model and know the feeling of what is was like being an early Madonna fan... it was such a ride.