'Harry Potter' strong heading into the weekend

Sequel rings up $21.9 million on Thursday

"Harry Potter and the Half-Blood Prince" continued to bewitch moviegoers Thursday as it took in an estimated $21.9 million at the North American boxoffice.

Piling that coin atop its opening-day tally of $58.2 million (including a record $22.2 million from its midnight previews), the Warners release has conjured up a domestic cume of $80.1 million in its first two days.

By comparison, 2007's "Harry Potter and the Order of the Phoenix," the only other Potter movie to open on a Wednesday, drew a first-day gross of $44.2 million and a second-day take of $18.4 for a two-day figure of $62.6 million.

"Phoenix" went on to pull in $139.7 million by the end of its first weekend, its fifth day in theaters, but "Prince" is already on track to score well above that number.