Before revision:  Moreover, we prove that for inputs given by random Gaussian algebraic branching programs of size (n,\delta), the algorithm runs on average in time polynomial in n and \delta. Our result may be interpreted as an affirmative answer to a refined version of  Smale's 17th question, concerned with systems of\emph{structured polynomial equations .
After revision:  Moreover, we prove that for inputs given by random Gaussian algebraic branching programs of size \delta Smale's 17th question, concerned with systems of\emph{structured polynomial equations .