PIS has about 30% support. Not enough to win elections. They had about 40% at their peak. It's enough to win elections but not enough to change constitution, which is why they break it constantly.
I don't think a revolution is a good idea. Would probably lead to thousands of deaths. If the next elections are marginally fair they lose and we go from that point. If they mess with the elections to the point of changing the result - at that point revolution is justified and will probably happen.