There are 5 tracking weeks left in the year after the current tracking week ends.
She's currently projected to sell 2.7 - 2.9M, but how much will she push before the year ends?

She already snatched the best selling album of the year from Taylor (currently at 1.76M)

For comparison, Taylor ended 2014 w/ 3.66 million.

And she has that NBC Primetime Concert Special in mid December.