I think one of the things the last ten years has re-taught us is that popularity is largely irrelevant in the wider case (especially of the sort done by polling firms in war zones), though certainly it can sway individuals - what is more important is control, either through military coercion or overriding popular legitimacy.

In the Afghan case, the Taliban was never popular in the Hazarajat, but it also faced no military challenge there once it had defeated the "United Front" in 2001.