Their record low at the new park when attendance was allowed was 1,338,851 in 1999. They have drawn 547,389 (18,246 per game) through today .
Assuming no additional rainouts and straight doubleheaders, they will need to average 15,519 per game the rest of the season to exceed that number. Likely already clinched it already between season tickets sold, and additional tickets sold for the Cubs, Yankees, Red Sox and Cardinals series.
That said, these are dreadful numbers during a "multi-championship window".