The figure was made public during the Nov. 8 "60 Minutes" segment on the Hamilton phenomenon. It's nearly double the $30.24 million that the upcoming London production, Harry Potter and the Cursed Child, Parts 1 & 2, rolled up in its record-breaking first few days on sale. Harry Potter doesn't open until next spring, while Hamilton has been open for three months, so the figures are not precisely comparable.
A spokesperson for the Broadway League would not confirm or deny the claim, saying the League does not track advance sale figures.
For comparison, the record holder for advance sale on a straight play is Larry David's Fish in the Dark. A spokesperson for an earlier megahit musical, The Book of Mormon, said the producers of that show do not disclose their advance sale publicly.