It will be interesting to see how China responds to this, after they recently elevated their relationship to an 'all-weather strategic partnership' (only DPRK is higher, iirc):

"China has always viewed its relations with Venezuela from a strategic and long-term perspective, and firmly supports Venezuela's efforts to safeguard national sovereignty, national dignity and social stability, as well as Venezuela's just cause of opposing external interference," Xi told Maduro.

"The establishment of an all-weather strategic partnership between China and Venezuela meets the common expectations of the two peoples and conforms to the general trend of historical development," Xi said, calling on the two sides to push for more fruitful China-Venezuela strategic cooperation, bring more benefits to the two peoples and inject more positive energy into world peace and development.

Doesn't seem to involve military support but I can't see China getting so close with Venezuela only to let the US take over.