  Cosmological relaxation of the electroweak scale via Higgs-axion interplay,
named as relaxion mechanism, provides a dynamical solution to the Higgs mass
hierarchy. In the original proposal by Graham, Kaplan and Rajendran, the
relaxion abundance today is too small to explain the dark matter of the
universe because of the high suppression of the misalignment angle after
inflation. It was then realised by Banerjee, Kim and Perez that reheating
effects can displace the relaxion, thus enabling it to account for the dark
matter abundance from the misalignment mechanism. However, this scenario is
realised in a limited region of parameter space to avoid runaway. We show that
in the regime where inflationary fluctuations dominate over the classical
slow-roll, the "stochastic misalignment" of the field due to fluctuations can
be large. We study the evolution of the relaxion after inflation, including the
high-temperature scenario, in which the barriers of the potential shrink and
destabilise temporarily the local minimum. We open new regions of parameter
space where the relaxion can naturally explain the observed dark matter density
in the universe, towards larger coupling, larger mass, larger mixing angle,
smaller decay constant, as well as larger scale of inflation.
