I wouldn't be so sure on that, I recently did some research with the help of this website:
http://www.electionpakistani.com/ge2013/result.html
What did I find? Politics of electables is still king outside of cities in Punjab. A candidate's personal vote bank combined with N league's vote bank got them the victory in 2013 elections. And there were a lot of seats where PTI wasn't even at second place, especially rural areas. The difference between first place and second place was around 30-50k for these second place candidates.
Now what's changed? The vast majority of those second place candidates a.k.a electables are now in PTI. So what can give PTI victory in the next elections? The same strategy N league used. Candidates personal vote bank + 20-30k vote bank of PTI.
That's why PanamaGate is so important. The PPP was damaged with the constant media barrage of corruption allegations during their tenure. Thanks to almost daily coverage of Panama issue which won't die down, even people from rural areas know what it's all about.
I will concede though, that people have short term memories, If this issue dies tomorrow N league may end up winning again.