Drug cartels are becoming very powerful in Mexico. Is it possible for them to officially take over Mexico?

To take over the entire government, I mean. Would it be possible for one or a few drug lords to officially call the shots? I know they now unofficially call the shots in Mexico. Government only has the power that the drug lords give to the government. Government in Mexico is extremely weak and the Mexico people are impoverished. The people are looking for a strong leader. Drug cartels are running the streets in most large Mexican cities and states right now. I really don't see what would stop them from taking over government and controlling Mexico's natural resources (such as oil). They could do it if they wanted to right now.