I kind of figured the lines would cross in June, but then I started to question my infallibility. Wait till a year from now when the economy is still in the crapper.
I suspect that the 34% "strongly approve" constitute the true believers and disciples, who will worship Evan Thomas's "god" right up till the bitter end. That number thus will not drop much further unless we have overt rebeliion.
The "strongly disapprove" numbers however, can only increase as outrages against the People mount, and the storm clouds gather. So yes, I think you are right, the lines will cross soon, as the bottom line rises.