I think by "simple" you mean Linear, which would consist of Source, R/L/C, and Transformers. Or as Engineers tend to label them "Electrical Circuits" as opposed to "Electronic Circuits" which have transistors/diodes. These circuits can have their responses written in terms of Linear ODEs.
The definitions get tricky, because as noted in the comments, you can have elements like an Op-Amp which we treat linearly, but it is actually composed on non-linear elements, in fact in the true sense the linear treatment of the op-amp is just an approximation.
If your question is strictly regarding amplifying the power of a signal using only linear elements, then no it cannot be done. You can try to understand this by viewing linearity of a circuit as equivalent to this statement "the R/L/C of each element does not change for a change in input voltage or current", and so of course that prohibits us from amplification.
However, we can introduce new elements with their own Transfer Functions (such as the Op-Amp) that perform linear amplification for us just the same. Notice though you cannot write the response of an Op-Amp in terms of an nth order Linear ODE, but you can when it is hooked up in some configuration that we use our Linear approximation for.