Maduro's biggest threat comes from within the Chavistas

While many media are focused on the government vs opposition battle, realize that one of the biggest issues continues to be the battle for control inside the government. Maduro's biggest threat does not come from the opposition but remains internal to the PSUV. The protests, along with deteriorating economic and security conditions, expose his poor leadership and make Chavistas wonder whether he is the correct person to be leading the country.
Who could replace him? Maduro isn't sure...